Archive of Our Own

Chapter Text

The Mystery Shack had seen better days.

Last week, Mayor Belos had finally found a legal loophole that let him confiscate the deed to the Shack. He’d called it a ‘danger to the public’ (even though creating a vampiric apple tree had totally been an accident! Probably. Luz hadn’t let Eda borrow the journal again, just in case.)

So Belos had stolen the deed, but Luz still had the Journal, which was what he really wanted. That’s why his nephew, Hunter, had stolen Amity’s secret giant robot, using it to try and capture Luz. He’d chased her off a cliff, crashed the robot, and finally felt bad enough to give her back the deed.

Pretty typical summer vacation, right?

But it was still worth celebrating, so they’d thrown a massive party last night. Except that somehow, Luz had sort of maybe used the journal to summon a zombie hoard – which was also an accident! She’d only meant to summon one or two zombies. If they sung horrible karaoke, maybe everyone else would feel more confident and join in.

It turned out Gravity Falls had a lot of zombies.

The townsfolk fled, but Eda, King, and Luz had managed to beat the zombies with some truly horrendous karaoke, proving that karaoke was a curse upon humanity once and for all. The fight had left giant fissures in the front lawn, some of them twenty feet deep. The grass was covered in gobs of zombie goo. And Masha, the Shack’s one and only cashier, had been thoroughly zombified.

Thankfully, the Journal had a recipe for curing zombification. Luz had immediately called her friends for help. While Amity led Masha around the yard with a raw steak, Luz, Willow, and Gus persuaded King to let them use his ‘favorite bath tub’ (which was really just a megasized metal bucket). They’d filled it with Zom-B-Gone shampoo, lured Masha in, and were currently scrubbing her within an inch of her afterlife. King was sitting on the porch, watching the madness and eating a bowl of leftover popcorn.

“This – isn’t – working!” Gus grunted, catching Masha’s hands before she could claw his eyeballs out.

“Luz!” Amity panted. “Are you sure we have all the ingredients?”

“Yes! Look – formaldehyde, cinnabar, werewolf fur –”

“You’re welcome,” King called from the porch.

Amity leaned over, squinting at the journal. “Luz, that says ‘cinnamon.’”

“Oh – oh, shoot, sorry! Be right back!”

Luz jumped up and ran inside. Eda was straightening furniture in the living room, still in her bright pink party dress. The wall phone, which had a cord and was therefore ancient, was pinched between her chin and shoulder as she wrestled the armchair upright.

“Yes, I need construction work done! Or landscaping. Whichever will fill giant holes in the ground. Actually, yes, this was definitely another giant robot attack, so feel free to bill the Mayor and his demon spawn –”

Luz darted around her and into the kitchen. The zombies hadn’t done much damage in here, too concerned with eating human flesh to think about actual food. She went for the spice cupboard, grabbed the cinnamon, and sprinted back outside.

Masha was now halfway out of the tub, her slate-gray skin covered in suds. Amity and Gus held her wrists, while Willow strong-armed her slowly back down. It was hard to tell the way her glasses flashed, but she almost looked like she was having fun.

“Back, back ye beast!” she shouted. “Back to the tub from whence ye came!”

Yep, definitely having fun.

“I got the cinnamon!” Luz called, pounding down the steps.

Amity looked up. “Great, add it in, hurry!”

Luz popped open the lid and dumped the entire container into the tub. Gus, Amity, and Luz plunged their arms in, swirling it around, then grabbed their sponges and sloshed it over Masha. Steam began to rise from her clothes. Her eyes glowed bright yellow.

“I win!” Willow said cheerfully, and she shoved Masha completely underwater. The sticky fluid gushed over the sides, drenching all four of them. More steam billowed up, so thick none of them could see the tub anymore.

“You better not have ruined that!” King snapped.

Luz coughed. “Did it work?”

The steam dissipated slowly. Then, out of the vapor, a dark shape rose ominously. Its spine was straight and stiff. Its arms were held straight out in front of it. It opened its mouth and cried –

“I LIIIIIVE!”

“Oh thank god.” Amity flopped back onto the grass, spread-eagled.

“Masha!” Luz grabbed her shoulders, checking her over. “Are you okay? Do you have a heartbeat? Are you hungry for fresh juicy brains?!”

“Please don’t phrase it like that,” Gus said faintly.

Masha groaned and rubbed her eyes. “I’m okay, I think? But my head is killing me. Metaphorically,” she added quickly. “Oh, wait, my nails are ruined! I spent twenty dollars on those!”

“That may have been the acetic acid,” Willow said thoughtfully.

Masha sighed and heaved herself out of the tub. They all lay on the grass to catch their breath. Luz could still hear Eda banging around inside. She was by turns bribing and threatening people to come fix the lawn. It sounded like some of them thought Mayor Belos had been right, the Shack really was dangerous to the public, and they didn’t want to come. The rest of them probably thought they’d get eaten by a stray zombie.

“Eda’s gonna make us do free child labor, isn’t she?” Gus groaned.

“No way.” Amity rolled over and buried her face in Luz’s side. “Too tired. Must sleep.”

“Must shower,” Willow corrected. “Then food, then sleep. I hope none of the gaping chasms hit the water pipes going into the house.”

“What did you use to fill the tub?” Masha asked.

“The garden hose.”

“Oh, yay, sewage. Are you sure I’m not still a zombie?”

“Still a what?”

All five of them sat up. Hunter stood a short distance away, looking vaguely alarmed.

“YOU!” Amity shot to her feet.

Hunter jumped back and almost fell into a chasm. “Whoa, hey, easy! I come in peace!”

“Yeah, right!” Amity stormed towards him. “You stole my robot, you kidnapped my girlfriend, you stole her aunt’s deed –”

“My uncle did that! I gave it back!”

“Can you give back all the weeks and months I spent on my giant robot?! That was my first ever original invention, and you just piloted it off a cliff and crashed it!”

“Batata, careful!” Luz scrambled over. Amity was slowly forcing Hunter back between two parallel chasms, and she’d really rather nobody find out what was at the bottom.

Hunter scowled. “I didn’t mean to crash it, I was just trying to catch Luz.”

“After you cornered her on the edge of a cliff –”

“I know and I’m sorry, okay? Look, I’ve been cleaning it up. If you want them I can bring all your robot parts back to your secret lab, or whatever.”

“ ‘Cleaning it up?’” Gus echoed.

Luz blinked, then looked closer. Hunter was still wearing the same clothes he’d had on when he stole the robot – a white collared shirt and khaki pants. But now they were wrinkled and covered in dirt, and his arms were so scratched he looked like he’d stuck them in a blackberry bush. A pair of dirty work gloves stuck out of his belt.

“Hunter,” she said slowly. “Have you been clearing all the robot rubble by yourself?”

“What’s going on out here?” Eda poked her head out the front door. “Oh, hey, it’s the demon spawn.”

“Hey!” King yelped. “I thought I was the demon spawn!”

“You’re my demon spawn. That’s just regular demon spawn.”

Hunter rolled his eyes. “If you want my help, stop calling me that.”

Eda snorted. “Why the heck would I want help from you?”

He pointed. Parked at the edge of the clearing was a large yellow construction vehicle. It had a wide scoop in front and a weird metal arm in back, like a scorpion tail with a smaller scoop at the end.

“I rented a few other vehicles to help me clean up the robot stuff. Then I heard about the party, I figured you could use one.” He frowned at Eda. “You are certified to use this, right? The company said you’d driven one before. Well, technically they said you stole it, but –”

“Mama’s certified! Mama’s so certified!” She scooped up King and practically sprinted for the vehicle, both of them cackling maniacally.

Gus winced. “Yeeeah, that’s not gonna end well.”

Luz turned back to Hunter. “Are you actually trying to help us?”

Hunter’s face reddened and he crossed his arms. “Look, Belos only went after the Shack to get your journal. I thought I was helping. I didn’t mean to take it that far.”

Amity glared at him. “But you did mean to steal my robot.”

“Not permanently! I was going to give it back! And I really think I’ve found all the pieces. I’ve been checking them against the blueprints you left in the operating hub. Except, Uncle keeps telling me I’ve missed something and to keep looking, so I was wondering if…you…”

He trailed off, staring. Luz followed his gaze. She’d dropped the Journal in the grass beside the tub. It had fallen open to a diagram of a mechanical tree, with steps around the trunk leading down into a bunker.

(Luz had traced over it in bright purple gel pen. Now a stick-figure Amity and stick-figure Luz walking down the steps, with a note that red ‘Secret Bunker of Love!!!’)

“Oh no you don’t!” Amity said, just as Luz yelled “That’s private!” and snatched it up.

Hunter held up his hands. “I wasn’t going to take it again! I just recognized that tree, that’s all!”

Willow looked up. “You did?”

“Yes! I found the robot’s foot next to it last night. There were magnets in the joints that kept dragging it back to the tree. It was a nightmare to pull it off.”

Gus frowned. “And you didn’t think that was weird?”

“Eda’s got a werewolf for a nephew and zombies chopped up your front lawn. Magnet trees don’t crack the top ten.”

“ Wait – ‘last night?’” Luz echoed. “Hunter, have you slept at all since you crashed the robot?”

“No, why?”

“Are you saying,” Amity said slowly, “that you can actually lead us to the secret high-tech bunker right this second?”

“Yes?”

“But, sleep!” Luz protested.

“Also food!” Willow added.

Gus held up a hand. “Or, actually, we grab some snacks and leave right now before Eda puts us to work.”

They looked over. Eda was driving wildly around the edge of the lawn, scooping up mounds of dirt, grass, and zombie goo and piling them into letter-shaped mounds. The letters spelled ‘BELOS SUX.’ King was riding inside the small scoop at the back, half-shifted into wolf form and bellowing challenges at terrified squirrels.

“Leave now, sleep later,” Luz decided.

Masha lay back down and waved an arm. “You kids have fun. Don’t do anything Eda would do.”

“No promises!”

They reached the mysterious Bunker Tree two hours later. Luz had grabbed Eda’s old volleyball jacket so she’d have somewhere to carry the journal. Then they’d stopped by the Diner for food and caffeine. Hunter, it turned out, had a special coffee order that was more caffeine than liquid. He ordered one for each of them to wake them up. Willow and Luz thought it was too bitter, Gus added sixteen creamers before drinking it, and Amity downed it straight and asked for seconds. (Luz was mildly concerned. Hunter was impressed.)

The actual bunker tree looked almost like all the other trees. It was tall, with branches that started at least two stories up the trunk, crusted with enough dirt and moss that it blended almost perfectly into the forest. The only odd part was the metal lever, hidden almost out of sight just above the lowest branch.

Willow volunteered to climb the tree. She shoved the lever with a grunt, and the whole tree shuddered. The ground around the tree dropped, like someone had shoved a donut straight down around the trunk. Steps emerged from the sides of the tunnel, leading in a spiral to a door at the base.

Amity’s eyes practically shone with excitement (and caffeine). “This is so cool!”

Hunter looked at it uneasily. “Does the Journal say what’s down there?”

“Oh, uh –” Luz made to open the journal, but Amity had already grabbed her wrist and was pulling her down the stairs.

Gus patted his shoulder. “Guess we’ll find out.”

The air in the staircase grew warmer as they descended. All of them took out their cell phones to use as flashlights. When they reached the bottom, automatic lights turned on, and they stepped into a large, metal-walled room.

It looked like a bunker from an apocalypse movie. There were pipes snaking all over the walls and ceiling. Metal shelves laden with supplies had been nailed to the righthand wall, with a dirty cot shoved underneath. More shelves stood against the left wall, this one holding dozens of boxes each labeled with a year, all the way up to 2070. An army-green closet stood against the back wall, with ‘WEAPONS’ painted across its doors in dull red paint.

Willow and Amity ran straight to the weapons closet and pulled it open.

Willow gasped. “Guys guys guys, there are weapons in here!”

“So many weapons!”

“They have a mace!”

“And a pez dispenser! And a taser!”

“Omigosh Amity, combine then! Combine them for the sake of science!”

Hunter looked at Luz. She shrugged and smiled weakly.

“Uh, girls and their toys?”

“Hang on.” Gus circled around the weapons closet. There was a map of Gravity Falls taped to the wall next to it. Gus pulled the map carefully away from the wall. The map had been hiding a large, rusty hatch. It wasn’t locked. Gus pulled it open with a grunt.

Willow gasped. “Are there more weapons down there?!”

“Wait a minute.” Hunter grabbed a box from the lefthand shelf and wedged it against the hatch, pinning it open. “There. In case it closes on us.”

“I’ll go first!” Amity tucked what looked like a Cosmic Frontier laser into her belt, then crawled quickly down the tunnel. Gus went next, then Willow, Hunter, and Luz.

The tunnel opened into an all-metal room. The floor, walls, and ceiling were all made of tiled metal. Some of the tiles engraved with symbols Luz recognized from the Journal. The tiles were almost all red with rust, and there were thick cobwebs stretching across the ceiling.

“It’s like an inverted Rubik’s cube!” Amity exclaimed eagerly.

“Yeah,” Willow said slowly, following her out. “But why isn’t there another door? What’s this room for?”

“Maybe it’s a prison,” Hunter said uneasily.

Luz crawled out last, already digging out the Journal. “Looks like it’s part of the security system. I think the metal tiles are supposed to just out and crush you like square-shaped teeth.”

“You know, at this point I’m not surprised.”

Amity was squatting next to a tile at the center of the room. Unlike the other tiles, this one wasn’t made of metal, so it hadn’t rusted. It was smooth, gray, and looked almost like clay, engraved with a triangle set inside a circle.

Gus sighed. “Please don’t push the button. I don’t want to get eaten by machine teeth.”

“I’m just looking!”

Hunter began walking along the walls, frowning at the symbols. “Why would there be a security system after the bunker? Wouldn’t it make more sense to put it first, at the start of the tunnel?”

“Oh!” Luz flipped the page. “There was something else after this, I think. Some kind of secret lab? Yeah, here it is! ‘Experiment –’”

“There’s a lab?!” Amity squealed, springing to her feet. Her wrist hit Willow’s arm. Willow, who had been absently tapping her new mace against one palm, startled and dropped it.

It hit the center tile.

Immediately all the symbols on the tiles flashed red. An alarm blared. Vibrations shook the room like they were standing at an earthquake’s epicenter. Hunter stumbled into a wall and barely managed to catch Gus before he fell. Several tiles began moving, jutting out slowly from the floor, ceiling, and walls, like a pixelated jigsaw of death.

“I’m sorry, I’m sorry!” Willow cried.

Hunter shoved Gus and Luz towards the center of the room. “Luz, the journal!”

“I’m on it, I’m on it!”

Amity whipped out some tools from the weapons closet and began jamming them against the moving metal. They groaned ominously as she leveraged them in place. Willow scooped up her mace. She began hitting the rods, smashing the rusted metal into powder, but the sections that had been inside the wall were still strong and rust-free. Luz flipped frantically back to the page on security features. It just showed a honeycomb-like diagram of weird symbols, but when she dug out her blacklight, four of them lit up.

“Guys! We have to hit these four symbols!”

“Got it!” Willow parkoured off the nearest rod and hit a symbol on the ceiling.

Amity whipped out a knife and threw it at the second symbol.

Hunter slid under a moving rod and hit a symbol next to the floor.

Gus found the last symbol and slapped with both hands.

A door slid open on the far wall, already half-obscured by the maze of moving rods.

“Run!” Luz shouted, and the five of them scrambled towards the exit. Willow grabbed Hunter and Gus and ran. Metal rods banged Luz’s elbows and head. Amity grabbed her by the jacket and dragged her through just as the trap closed behind them. The five of them collapsed in a heap, breathing hard.

“Did we die?” Gus gasped.

Willow laughed shakily. “If we did, we’ll need some more cinnamon. Luz used it all on Masha.”

Hunter sat up with a groan. “Someone please tell me we can open that room again, or we’re going to need another way out.”

Luz rolled to her hands and knees. “Good point. Amity, do you think you could – oh.”

The room had a few rolling desk chairs and a metal door set into the far wall. But most of the room was taken up by two massive computer bays. There were dozens of screens along the left and right walls. It was the weirdest mix of time periods Luz had ever seen. The ones on the right had old-fashioned film reels mounted on them, and the lights and buttons were definitely pulled straight from the sixties (or seventies or whenever dinosaurs were still alive). But the keyboards had symbols Luz had only ever seen in Amity’s textbooks, and when Amity started tapping on them, the monitors lit up with a rapid succession of text, mathematical diagrams, and what looked like security footage.

“This is amazing!” Amity gushed. “They even use Euler’s number as the power button, it’s so intuitive, and it looks like they used geothermal energy to power it, I can’t believe how efficient it is, I’ve never seen anything with this much RAM –”

“Aaaand we’ve lost her,” Willow said, grinning.

“Hey, I found the Rubik’s cube of death in here! Let me switch it off real quick. Oh, check out this cooling system, they even designed their own coolant –”

Hunter, who had rolled into a kneeling position, moved to stand up. His shoulder hit a metal desk corner and he sat back down, hard.

“Hunter?” Gus and Luz asked, alarmed.

“’M fine,” he snapped. “Just dizzy. The air down here is probably really stale.”

“It really is,” Gus agreed. He and Luz both held out a hand, but Hunter just gripped the desk and pulled himself to his feet.

“We should find another way out, just in case.” He started for the door in the opposite wall.

Gus frowned anxiously. “Luz, do you think he’s okay?”

“As in, safe to trust, or…?”

“We brought him with us, it’s a little late to worry about trust. But no, I meant…” Gus waved a hand vaguely. “I know he comes off as this, like, polished prissy golden boy? And I’ve only ever talked to him personally once, and then he went right back to his standard persona, so I thought it was a fluke or something. But now he’s kind of…”

Luz nodded slowly. She knew what Gus meant. The Hunter she knew was overconfident, bossy, and arrogant. The Hunter they’d brought with them had barely said six sentences, none of them orders, and hadn’t tried to show off even once.

Gus twisted his fingers together. “Maybe I should –”

Willow, standing next to Amity, suddenly gasped. “Wait, go back a screen! I think I saw a weapons system!”

“– make sure they don’t blow us up,” Gus finished with a sigh.

“I’ll check on him,” Luz promised. She made her way over to the door. Hunter had managed to pull it open. It wasn’t a way out, it just looked like some kind of closet. He was running his hands carefully over every square inch of wall.

“Hey, can you shine a light in here?” he asked as she approached. “I’m trying to see if there’s a secret opening anywhere.”

“Sure.” She pulled out her phone and stepped inside, letting the light of the screen fall over his hands.

The door slammed shut behind them.

They both screamed and she jumped back, slamming him into the wall. Jets of water shot down from the ceiling. She heard shouting from outside the closet. A blast of air shoved her and Hunter together, knocking skulls painfully, before there was a loud alarm and a new door opened on the other side.

“What the heck!” Hunter gasped.

“Luz!” Amity’s voice called through the closed door. Luz jumped to her feet and rushed back into the closet, but there wasn’t a handle on this side. She felt someone pounding through the metal.

“Amity! I’m okay! What happened?”

“I think we might have triggered something on accident, but I don’t know what we did!”

“We’ll figure it out,” Gus called. “The stuff on the screens moved pretty fast, but I saw what happened. I can recognize that menu again if we find it. Where’s Hunter? Are you both okay?”

“Fine!” Luz called on reflex. Then she looked over her shoulder, and her voice died in her throat.

The room was less like a lab and more like a cave, the rough stone curving in a dome around them. Pipes led to three vertical chambers on the opposite, like cryogenic tubes. Their blue glow was the only light in the place, casting long, fingerlike shadows from every rock and pebble. All three were empty. A large, round tunnel had been carved into the rock on the left.

On the right, next to a small, rusty computer, a long row of cages had been dug into the tunnel. The rock around the cages looked sharp and raw, like it had been cut more recently than the rest of the lab. There were at least five cages on either side. It was hard to tell from the dim light, but it looked like there were bits of paper at the bottom of the cages. The backmost cages were completely hidden in shadow.

The bars on the closest two cages had been bent outward, like something had burst straight through.

“Luz?” Amity called again. “I’m going back to the computer, okay?”

“I –” Luz shifted, and her foot hit something metallic. She and Hunter both jumped. The ground was littered randomly with cans of baked beans, all of them open and empty. Hunter reached down and picked one up. The lid dripped a thick, viscous, slightly green substance. It didn’t look like bean goo anymore.

Suddenly a low, rhythmic sound reached their ears. Luz realized it was the sound of breathing just before a drop of goo plopped at their feet. It had come from right above them.

“Luz,” Hunter whispered. “What did the journal say was down here?”

“C’mon, c’mon,” Amity muttered, typing frantically at the keyboard. Willow and Gus were still pulling frantically at the closet door. Had Amity hit a key and shut it? Had Luz and Hunter triggered a sensor? Either way, there had to be something on the system to release the lock.

Suddenly there was a long, rattling hiss on the other side of the door. Hunter and Luz began screaming.

“Amity! AMITY!”

“There’s a monster in here! Open the door!”

“I’m trying, I’m trying!” Amity cried.

The door banged like something was striking it from the other side. Willow reared back, mace in hand, but Gus grabbed her wrist.

“No, we could bend the lock and seal them in!”

“Or break it and let them out!”

“Them and whatever else is in there! If it just chases them in here they won’t be any safer!”

“Cameras!” Amity shouted, finally pulling up a menu for the security system. A computer on the wall behind her lit up with a view of the other side of the door. It looked like a mad scientist’s lab, with creepy cryotubes and everything. It showed Hunter and Luz just as they tore out of sight to the left. Something passed over the camera, too close to see clearly, but it looked like it had claws and way too many legs.

Willow clenched her fists. “Alright! Gus, you and Amity work through that computer menu and open this lock. I’m going to search for tools to use as weapons or lockpicks. Stay calm and move fast. Let’s go!”

Hunter and Luz ran through the tunnels. He hadn’t waited to see what dropped from the ceiling. He’d grabbed her wrist and took off as fast as he could. The blue light from the cryotubes threw their shadows out in front of them. Whatever was chasing them was long, bulging, and clawed.

“Slow down!” Luz gasped.

“Run faster!” he snapped.

The tunnel twisted. Metal piping glinted suddenly on their right. It looked like pipes had been set into the wall, one of them with a metal wheel like a water pipe.

The bulging shadow shifted. He ducked left and something whipped past his neck. Luz screamed. He heard the squeal of sheared metal. The monster had aimed for his head, missed, and cut through one of the pipes, slicing out a piece two feet long. He scooped it up and swung, hard.

There was a nasty squelch. The thing reared with a howl, falling fully into the dim blue light. Hunter choked on a scream. It was long, snakelike, and sickly pale, like a fish left too long in the dark. Its wide mouth was full of sharklike teeth. As Hunter watched, a chunk of flesh bulged out of its shoulder, twisting and cracking until it formed a many-jointed leg tipped with a black claw.

“Watch out!”

Luz yanked Hunter back. The claw tore through the air where his neck had been. The two of them turned and sprinted farther down the tunnel, Hunter still gripping the pipe.

“Luz, what the heck is that thing?!”

“How should I know?!”

“You didn’t check your journal?!”

“I know, I’m sorry!”

The monster let out a cry. Hunter risked a glance behind them. The thing had crawled straight up the wall and was now chasing after them on the ceiling. Its shadowy form seemed to ripple and shift. A tunnel opened to their left and Luz shoved them both into it right before a long tongue shot from the thing’s misshapen head.

The new tunnel was set on a steep incline. Hunter’s foot slipped and they both went tumbling down the slope, banging their heads and elbows on the walls, floor, and each other. They landed in a heap at the bottom. It was pitch-black; even the faint light of the lab was gone. They heard a scuttling, raspy breathing.

“I’m going to find you!” it cackled. Its voice turned sickly sweet. “Won’t you come out to play? The other one won’t play with me anymore.”

Other one? There were more?!

Hunter felt Luz’s hands grab his arm in the dark. He pressed them both back against the wall. The thing was coming, scrabbling and scuttling and knocking dirt and pebbles loose as it went. He dug into his pockets with his free hand. He’d been doing construction clean up for forty-odd hours, it had only made sense to keep a few things handy. A multitool pocket knife, a small first aid kit, a flashlight with dead batteries, and an inflatable water bottle. Nothing big enough to do damage. He leaned over until his mouth was next to Luz’s ear.

“Phone,” he whispered, very quietly, desperately hoping she understood.

The thing laughed again, much closer. The sound sent a chill into Hunter’s lungs. “You won’t play with me, either, will you? That’s alright. After all, it’s been so long since I’ve had anything besides those awful beans. And I’m so hungry.”

It lunged out of the darkness. Luz thrust her phone directly into its face, flashlight cranked to maximum. The thing reared back with a scream. Spiderlike legs sprouted from its back and neck to cover its eyes as it screamed in agony. Hunter felt like screaming, too, but he’d already grabbed Luz’ hand and run back up the tunnel, pumping his legs as hard as he could.

“It’s gonna eat us!” Luz gasped.

“We need to get back to the lab!”

There was another roar down the tunnels.

“Turn on the light again!” he ordered.

“It’s gonna find us!”

“It’ll find us anyway! There were pipes ahead. If they still work we can flush it away!”

“What if it just grows gills?!”

“Do you have a better idea?”

From her grunt, he knew she didn’t. She turned on her phone and held it out. The light bounced badly around the tunnels, making every shadow jump like the monster had somehow gotten in front of them. He ran faster. He was practically dragging her after him, but that was fine as long as neither of them tripped. There – the pipes were just ahead. He let go of Luz and ran full-throttle at the metal wheel, using his momentum to grab and jerk the wheel as hard as he could. The rusted metal groaned but didn’t budge.

Luz swung her light around. The creature’s shadow appeared against the wall, twisting as it sprouted three new legs and a scorpion’s tail.

“Hunter!”

“I’m trying!”

Luz dropped the phone and ran over. The two of them gripped the wheel and twisted. Sweat poured down Hunter’s face. Come on, turn, please turn –

“FINALLY!”

The monster shot out of the tunnel. Its bulging eyes had turned pitch-black, glittering like an insect’s. It reared up, its mouth growing longer until its neck split open into an unhinged maw.

“When I’m done with you brats, I’ll wear your faces and slip right into town. Then I can eat everything and everyone I want!”

KSSHHH!

The wheel suddenly gave under their grip. Water gushed out of the open pipe beside them, shooting a pressurized stream directly into the creature’s mouth. It tried to scream but its mouth was full of raw sewage. Its arms clawed for them, but the water forced it back. Hunter had a split second of relief before a sharp, metallic groan reached his ears. He shouted and tried to grab Luz, but the pipes overhead burst. The blast slammed into his legs and knocked him off his feet. He and Luz went tumbling head over heels, water forcing its way into his mouth and nose and ears. He inhaled on reflex and coughed, inhaling more water.

It must have only been a minute or so, but it felt like an eternity before the water drained into the dirt walls. Hunter rolled to his hands and knees, coughing hard. Great. Now they were even farther from the lab and had just ticked off a carnivorous shapeshifter. A dim shape moved to his left and he heard a groan. He didn’t think, just bodyslammed it to the ground.

“Ow! Hey!”

“Prove it’s you, Luz!”

“You chased me off a cliff for the journal, now prove it’s you!”

“You threw a zombie party last night because of course you did.”

“What is that supposed to mean?!”

There was a low, rasping hiss from down the tunnel.

Hunter moved to get up and his hand hit something hard. The broken metal pipe. He grabbed it and felt for Luz, pulling her to her feet.

“Hunter, wait, we can’t take this thing!”

“We’re not going to. I’m going to slow it down. You run back and get help from the others.”

“But –”

“I said GO!”

“Chilllldrennnnn!”

It was getting closer. Luz turned and ran. He heard the spatter of her footsteps in the mud and yelled to cover the noise.

“OVER HERE, MONSTER, COME AND GET ME!”

He lunged forward, swinging as hard as he could.

Amity’s fingers flew over the keys. She and Gus had switched the lab lights on and off, rebooted the cryochambers in the next room, and activated a lavender-scented air freshener, but they still hadn’t opened the closet door.

“I take it back,” she muttered. “This is neither fun nor intuitive, just unlock the door already!”

Suddenly there was loud, desperate pounding against the door. “Hello!”

“Luz!” Willow rushed over. “Stand back, I’m bashing this thing!”

“Wait-wait-wait!” Amity pulled up a new screen. “There are security features if you do, but I think I can crack the passcode!”

“Please,” Luz sobbed. “Please, let me out, it’s going to come back –”

“Where’s Hunter?” Willow called.

“I don’t know, I don’t know!”

“Got it!” Amity pressed a button and the door slid open. Luz fell into Willow’s arms, gasping, tears streaming down her face. Amity rushed over to support her. “Luz? Are you okay, are you hurt anywhere?”

“Please, we need to go, we have to get out –”

“Guys!” Gus held up a clipboard. “Guys, this says ‘Experiment 210: The Shapeshifters’! I think we may have a whole new problem.”

They all looked at Luz.

She blanched. “I-It’s not me, it was chasing me!”

“Oh yeah?” Gus challenged. “Prove you’re Luz. What’s my favorite color?”

She blinked at him. “…Blue?”

He looked down at his all-blue outfit. “Okay, not the best question.”

Amity looked at her carefully. Was it just the lighting, or had her eyes always been that dark? And her hair was too long – after that botched haircut King gave her two weeks ago, it brushed her chin, not her neck.

“Luz,” Amity said slowly. “What are my older siblings’ names?”

The figure whimpered. She tried to pull away, but Amity tightened her grip. Willow hefted her mace.

“What are my older siblings’ names?”

“I-I don’t –”

“Edric and Emira!”

They all looked up. Luz – the real Luz – ran out of a tunnel in the left wall of the lab. She was soaking wet and streaked with dirt.

“Amity, Gus, Willow, get away! I think it’s another shifter!”

“No, wait!”

Not-Luz shifted under Amity’s hands. Amity leaped back. The shifter’s brown hair sucked into her skull until only a blue tuft was left on top. Her face flattened and her eyes bulged. Her clothes melted away into smooth, yellow-green scales. When she was done, she looked like a kind of snake-person, with a fish-like face, humanoid arms, and a tail six feet long. Amity tensed, but the shifter just put her hands over her head, shaking so hard the metal floor rattled.

“Please, I’m not going to hurt anyone! Nine – the other shifter – she’s trying to hurt me, too. I just want to leave, please, please!”

Amity glanced up and saw the look in Luz’s eye. “Luz, no, don’t you dare!”

“Alright, you can come with us when we go.”

“Um, no?!” Gus said incredulously. “She literally just tried to be you!”

“She’s telling the truth, the other shifter really is after her, too. And trust me, she’s nothing like the other one.”

“But –”

A roar echoed from the tunnel.

“Argue later, plan now!” Luz said quickly. “Guys, Hunter’s fighting it to buy time. We need a plan!” She stepped toward Not-Luz. “Listen, is there anything you can think of that will stop it?”

The shifter sniffed. “The c-cryochamber. She’ll be stuck in stasis until someone lets her out.”

“Great. Alright guys, how do we get her in there?”

They were in place five seconds later. Amity was by the supercomputers just outside the lab. Willow and Gus flanked the tunnel entrance. The other shifter was out of sight, tucked behind the computer by the cages. Luz took up her place in the middle of the lab. She would lure the other shifter over to the chambers, Gus and Willow would push her in, and then Amity would push the button to activate it.

It was a truly horrible plan.

But Luz couldn’t think of a better one. She just really, really hoped they could pull it off, and even more so that she’d made the right call about the other shifter. She’d just looked so scared. Maybe she was acting, but she’d been inches from her friends and she’d cowered instead of attacked. That had to mean something, right?

Wet thuds and the scrape of claws on metal echoed from the tunnel. Luz shoved all other worries to the back of her brain and waited, holding her breath.

Suddenly Hunter and the shifter burst into the lab, both of them locked around the metal pipe. He was struggling to whip the ends of it into the shifter’s face, but she had wrapped two clawed hands over his and was forcing him back. Its teeth snapped inches from his face. Its eyes gleamed with bloodlust. It forced him to one knee just as Luz ran forward.

“Hey! Hey, over here!”

“Live bait?” Hunter gasped. “That’s your plan?!”

“I told her it was bad!” Amity called.

The shifter spat green goo at Hunter’s face. He yelled and ducked. She shot over him and straight for Luz. Gus and Willow jumped forward, grabbed its tail, and dragged it back. It whirled with a hiss. Hunter rolled, knocking Gus down just as its tail cut through the air. It hit Willow in the gut and she doubled over, wheezing.

Luz scooped up a rock and threw it at the back of its neck. “Over here!” Luz shouted, darting for the cryochambers.

Something wrapped around her middle and threw her into the first cryochamber, hard. Glass shattered over her head. All the air left her lungs and she slumped to the ground. She heard Amity scream. Hunter jumped forward, whirling to stand between Luz and the shifter. The snake slithered forward slowly, almost sauntering, madness gleaming in its eyes.

“Well, well, well,” she hissed. “What a cute little trap. Perhaps I’ll save one of you in it for a snack. Now, should I be one…” She morphed into Luz, but her teeth were just a little too sharp, her hair too tangled. “Or the other?” Her version of Hunter was even more disturbing, with pointed ears and black sclera. Not-Hunter’s grin widened until its lips split. “How about both?”

It shifted again, its skin bubbling and melting as it fused the two forms together in a twisted C-shape. Not-Hunter’s torso dangling upside-down as Not-Luz’s torso rose up from the middle. Spidery legs sprouted from the middle where the two forms were joined. It roared, the eyes and mouths on its faces glowing a poisonous blue.

“Nope!!”

Willow’s mace swung straight into Not-Luz’s jaw, which caved around the metal like wet clay. The shifter grunted, then smiled horribly as Not-Luz’s arms reshaped into thick tentacles that wrapped around Willow’s wrists and arms, dragging her into its body.

“Get off of her, monster!” Hunter darted forward and swung for its waist, forcing the shifter to disgorge her.

“You little –”

One of its tentacles lashed out, slamming Hunter into the second chamber. The pipe fell to the ground with a clatter. The glass chamber cracked and steam hissed from the top.

“ ‘Monster, monster!’” it mocked. “You stupid little boy, why don’t I show you a real monster?”

It grew, doubling in size. Long, gray-blond hair sprouted from its head, reaching past its shoulders. Its ice-blue eyes burned with madness. A pale cloak streaked with filth billowed from its neck. A thick black mask covered the bottom of its face, but it was very clear who it was meant to be. The caricature of Mayor Belos loomed over Hunter and he fell back with a scream. Bony hands flew up from under the cloak, reaching for his throat –

“EAT THIS, SUCKAH!”

Luz grabbed Hunter’s pipe and smashed it as hard as she could into Not-Belos’ guts. It lodged deep, just like Willow’s mace, but suddenly Amity there, shoving Luz back and pressing her futuristic taser against the metal. A loud buzz filled the air a split second before the shifter’s body spasmed with white lightning. The taser shorted out and it staggered, gasping airlessly.

“Push it in!” Willow called.

Luz, Amity, and Willow shoved it as hard as they could. It fell heavily into the third chamber. With a sudden hiss, the cryochamber closed. The three of them jumped back to avoid the door. A thick mist spurted from the top of the tube. The shifter gave a muffled howl as the inside glass frosted over. Luz turned to see Gus standing by the computers, fingers over the keys.

“Did we get it?” he called.

Luz opened her mouth to reply.

A hand slammed against the glass. They fell back with a scream. The shifter’s face, still morphed into Belos, pressed itself through the mist.

“You think you’re so clever!” it snarled. “You have no idea what you’re up against, what other monsters are out there. If you keep digging, you’ll face horrors worse than you can imagine, and you’ll wish I’d eaten you alive! Do you hear me!? You’ll wish I’d –”

The mist froze with a crackle, sealing over the shifter’s body in a pale blue frost. It didn’t move again.

Gus whimpered.

“Is – is everyone okay?” Willow panted.

“How did it do that?” Hunter gasped, leaning heavily against the second chamber, staring up at the shifter. It had frozen with the mayor’s face still twisted in rage and hatred. “How did it know what he looked like?”

Luz swallowed. She had a sinking feeling about who had been bringing down all those cans. She took a deep breath, then turned and walked towards the computer by the cages. Willow, Amity, and Gus followed. Hunter followed more slowly, like he was made of glass and was next in line to shatter.

The other shapeshifter was right where they’d left her. She had squeezed her eyes shut and clamped both hands over her mouth to muffle her crying. Luz’s heart twisted. She knelt down in front of her a few feet away.

“Hey.”

The shifter jumped. “I-I’m sorry, I didn’t want to shift, I wasn’t going to hurt anyone –”

“Hey, hey.” Luz held up her hands, backing up a step. “No one’s going to hurt you, either, okay? Can you tell us your name?”

The shifter uncurled slightly. “I’m number fi – I mean, I’m Vee.”

“Okay, Vee, we’re going to get you out of here.”

“We are?” Amity asked.

Luz gave her a Look.

“Okay, fine! Pardon me for being protective.”

Luz smiled and turned back to Vee. “See? You’re coming with us. But can you tell us what happened, or how you got down here?”

Vee swallowed. “I-I think my kind went extinct, but there were a few of us saved in the cryochambers as eggs. The man hatched us and kept us here.”

“The man?”

“Yes. He wanted us to shift. But our eggs had been dormant for decades, and not all of us could. H-he took the others away, until it was just me and Nine. He kept his face covered so we couldn’t shift into him, but he showed us other pictures to use as practice. Then Nine stole his lunch and shifted into a perfect cow. That’s when we learned the only way to shift perfectly is to eat what we shift.”

“That’s…interesting,” Gus managed.

Vee hunched. “I just ate the beans. But last time he came by, he gave us two pictures to practice with. H-he said he’d send the real things to us, and when we shifted into them, he would bring us to the surface. But Nine was too hungry to wait. She broke out of her cage and into mine. She said if she ate me, she’d be strong enough to shift and burrow through the bedrock. I’ve been hiding from her in the tunnels ever since.”

“Photos?” Willow asked.

The scraps of paper. Luz glanced at Hunter. He turned and moved silently to the cages. There were exactly two scraps, one in each cage. He held them up. One was a picture of Luz, when she was trying to bathe King in his bathtub on the lawn. The other was a school photo of Hunter, taken earlier this year.

“This is crazy,” Willow said quietly, staring at the photos. “So you were all just trapped down here? And you and the other shifter – Nine – were supposed to just…replace Hunter and Luz? Why? What about afterward, how was he supposed to keep you from shifting into anyone else?”

Vee hesitated. “I don’t know, but the beans started tasting funny. Everything felt fuzzy when I ate them.”

Gus blew out a breath. “So we’ve got captivity, planned murder, and mind-controlled beans. Great. Am I missing anything else?”

“One,” Amity said quietly. “Though I think we know the answer. Vee, can you describe the man who did this?”

Vee pointed to the cryochamber, where the frozen shifter still wore Belos’ face.

The group was quiet as they ascended the metal stairs. The sun was just beginning to set, and the light had turned a soft pink, bathing the trees in a rosy glow. The wind that whispered through the branches carried the fresh scents of pine and soil. They filed out of the staircase, Hunter bringing up the rear. Luz stopped and took a deep breath. She smelled pine needles and clean water and rich soil. It was so peaceful made Luz want to cry.

“What…what is all this?” Vee whispered. She’d been clinging to the back of Willow’s shirt the whole time, barely saying a word.

“It’s a forest,” Luz said quietly. “Don’t worry. The man who hurt you is very far away.”

Vee shot a quick glance at Hunter. “Are you sure? It’s just, he smells like the man…”

“Hunter is his nephew,” Luz explained. “The smell probably rubbed off on him, that’s all.”

Amity scrubbed at her face with her hands. “This stinks. All that incredible technology, years ahead of its time –ahead of our time – and I couldn’t even enjoy it because we were fighting for our lives. Can we have just one summer adventure with no death in it? Like, the ice cream truck breaks down and I fix it. That’s our next adventure.”

“I’ll let the universe know,” Gus said wryly.

“We could probably make it happen,” Luz said thoughtfully. “Maybe use all the spare robot parts to make an ice cream truck.”

“Hasn’t my poor robot child been through enough?!”

Luz grinned and looked over. “Hey, Hunter, do you think you could – um.”

Hunter was still staring at the tree. He hadn’t moved, but his hands were visibly shaking. He muttered something under his breath.

“What?”

“I can’t go back,” Hunter repeated. “I can’t – I can’t go back. I can’t go back. I can’t go back. I can’t –” He doubled over, wheezing, arms pressed to his stomach.

“Whoa – hey!” Luz hurried over. To her surprise, Gus ran to his other side and put a hand on Hunter’s back.

“Hunter, man, you gotta breathe.”

“This – he wanted me to find this, this is what he meant –”

“Yeah, probably.”

Hunter tried to say something else, but it didn’t look like he could get enough air. Luz made a quick shooing motion to Willow and Amity. Gus grabbed one of Hunter’s arms, Luz took the other, and the two of them pulled him to a nearby log. As soon as they sat him down, Gus gently pressed on Hunter’s shoulders until his head was between his knees.

“Deep breaths, like I showed you,” Gus coaxed. “Breathe in, one, two, three, four. Out, one, two three…”

When did Gus show him that? Luz wondered. She made a mental note to ask later.

She sort of wished they hadn’t sat down. Now that she had, she suddenly noticed how much her legs hurt from running. Her head pounded from the aftershocks of pure terror. Watching Hunter struggling to breathe made it worse. The two of them had nearly died, but that wasn’t even the worst part. The worst part was that someone had tried to plan their deaths.

At least she had friends and a home to go back to. What did Hunter have? They couldn’t even go to the police. They hadn’t done anything to stop Belos before, and there was nothing down in the bunker they could use as proof. Unless they were willing to listen to Vee. And from what she’d hinted at, Luz didn’t want her anywhere near town where Belos could find and capture her again.

Luz’s head pounded harder. She tried to focus on Gus’ counting and breathe along with them.

“Hey.” Willow stepped around a tree, Amity and Vee lagging behind her. “Are you three doing okay?”

“No,” said all three at once.

“I need to go,” Hunter croaked.

Luz frowned. “Where?”

“They could come back to my place,” Amity offered. “There’s like, a billion rooms we never use. My mom thinks you only use all the rooms if you’re poor. There are whole closets the size of apartments.”

Gus made a face. “Yeah, but servants probably clean those.”

“Oh…”

Willow rolled her eyes. “My family has a cabin in the woods. It’s like, ancient, and I don’t know if the lights or the plumbing still works, but it’s got four walls and an old-fashioned stove. Hunter and Vee could stay there. We could bring them supplies tomorrow.”

Vee tensed. “I’d stay with him?”

Hunter flinched.

Luz patted his shoulder. “Hey, I promise, Hunter’s a good guy. But if you’re not sure, you can always come back to the Shack with me. Actually, you two could probably visit to resupply, as soon as we make sure Belos can’t take stalker photos anymore. Eda’s been meaning to upgrade security anyway after that boy band stole all her trash.”

Vee blinked. “You know, on second thought, the cabin is fine.”

Luz grinned and pushed herself to her feet. She wobbled a bit and Amity reached out to steady her, then kept hold of her hand. Luz sighed and leaned into her. “Let’s just get going. The sooner we get out of here, the sooner we can all go to sleep.”

Willow really did have a family cabin, and it really was dusty and dirty. Willow led them to a spot about forty minutes’ walk due north of the Shack, where a tiny cabin the size of two garden sheds sat snugly between two oak trees. The lock had rusted shut, so Willow had had to break it open with her mace. They stepped in cautiously. Inside was nearly as dirty as the outside. There was a twin sized cot against the left wall and a small counter against the opposite wall. An old iron stove sat next to the counter. A bathroom sat tucked against the far right corner. There was a wooden chair next to the door, but the cushion on it had nearly disintegrated. When Gus poked it, a family of mice peeked out and squeaked at him.

Luz winced. “Well this is…definitely a cabin.”

Willow grimaced. “Yeah. It’s sort of a family inheritance. Gus and I used it as a hideaway when we were kids, but aside from that, no one’s been here since my great-grandfather’s time.”

“Oh, hey, that reminds me!” Gus went over to the counter and opened the cupboards underneath. He pulled out several colorful bags of chips. “I told you snacks would come in handy! Hex Mix, pizza-flavored Kingles, Flay’s Chips, we got it all. And it’s only like eight years out of date!”

Vee poked her head over Luz’ shoulder curiously. “What’s a chip?”

Gus gasped. “My good Vee, I have an entire new world to share with you.”

Luz grinned and stepped aside to let her through. “You can try anything you want. Chips like that keep forever, so they really should be safe to eat, but we’ll bring you more tomorrow. Where’s Hunter?”

Amity pointed towards the open door.

Luz stepped out, but she didn’t see him anywhere. She almost thought he’d left entirely until she heard noise at the right of the cabin. When she came around the corner, she found Hunter sorting through a rotted pile of chopped wood. The next log he picked up had some kind of moss-mushroom thing on the bottom. It opened an eye and glared at him. Hunter glared back and tossed it to one side. The log grew legs and the mushroom thing waddled off.

“Hunter?” Luz asked. “What are you doing?”

“What’s it look like?” He tore another piece of wood off the pile, then let go with a yelp. A scampfire crawled out of its hollow middle, spat cinders at him, then crawled back inside. “You know what? Fine! Keep the stupid firewood!”

“Do you want a hug?” Luz blurted.

“No, Luz, I don’t want a hug! I want to know why! I want to know what I did that made my Uncle want to –” He broke off, shoulders rigid, face twisted in pain. “Why didn’t you check the stupid journal before we went down there? Maybe – maybe it wasn’t Belos, maybe your dumb aunt did something, maybe –”

“She didn’t,” Luz said quietly. “I checked the journal. She’d tried, but she only managed to hatch one, and it looks like it went with her when she disappeared. She left the other eggs in the cryochambers to keep them from being ‘collected,’ whatever that means. And…in the drawings of her lab, there were no cages. It wasn't her. It was Belos.”

Hunter's face had gone ash-gray. He closed his eyes.

Amity stepped around the corner. “Luz, are you – oh.”

“Go away,” he snapped, but his voice cracked like he was trying not to cry.

Luz and Amity glanced at each other.

“For the record,” Amity said, “you didn’t do anything. I mean, you did, but – you did everything he told you to do. Sometimes people just want power over others, and they’ll twist and break you to get it. There’s nothing you did to deserve it. Parents aren’t automatically good people. You’re not bad for believing him, or for doing what you were told to survive.”

Luz gave a low whistle. “Geez, Blight, when did you get so eloquent?”

“When I got a girlfriend who said I could be better than my parents.”

Luz sputtered. “You – I can’t – I have had too many emotions today, you can’t just drop romance on me when I’m not ready!”

Amity grinned and looked at Hunter. “Just to forewarn you, you will see me be a lot sappier now that you’re one of us. I will neither explain nor apologize.”

Hunter blinked. “One of – ?”

“Guys?” Willow called. “I hope I’m not interrupting, but it’s kind of getting dark.”

“Coming!” Luz called.

“Yeah, yeah.” Amity slung an arm around Luz’ waist, paused, then glanced back. “And thank you for saving Luz. I forgive you for destroying my robot.

Hunter sputtered, but Amity was already tugging Luz away. Willow and Gus were waiting for them in front of the cabin. Luz glanced behind her to see Vee standing in the doorway. She looked nervously between them and Hunter, then leaned out cautiously. Luz couldn’t hear what she said, but she saw Hunter hesitate, then follow her inside.

“I feel like I just lived through a week of stuff in one day,” Gus grumbled. “So, we found a scary lab, fought a shapeshifter, and brought a different shapeshifter home like a noodle-shaped puppy.”

“And I got a mace!” Willow said brightly.

Amity nodded. “And tomorrow we’re bringing the Trauma Twins all the snacks I can steal from my family’s spare kitchen.”

Gus gasped, realization dawning on his face. “Do you mean, all this time, you’ve had access to infinite ingredients? I could make so many recipes!”

“I still have to sneak them out!”

“You snuck giant robot parts out of your father’s lab, I’m not concerned. Hang on, I’ll write a list –”

Amity groaned and Willow smirked, shouldering her mace. Luz smiled weakly. She was deeply grateful for her friends’ chatter. She didn’t want to think about what had happened today. It was too big, and it hurt, and she felt like all her nerves had been scraped raw. She’d think about it later. Maybe. When she was buried under a mound of blankets with King in her lap and Eda’s arms wrapped around her like she’d never let go.

She closed her eyes, leaned into Amity, and let her friends’ voices lead her home.