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Part 2 of Robin’s Apprenticeship (And Its Unintended Effects) , Part 2 of All of My Apprentice Fics
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Published:
2026-07-03
Updated:
2026-08-07
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30,554
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7/15
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Truth Serum

Summary:

“You can’t ask me anything, Star. There are things I can and cannot say. Don’t let them hear me. Don’t let the others—”

“Robin,” Starfire said firmly, her hand now holding onto his. She squeezed it. “You are safe now. I will protect you. I promise.”

Robin gets hit with truth serum during a mission.

Suddenly, every secret he's ever sworn to protect is only one question away from being exposed.

And when memories of an apprenticeship that should have never happened begin to resurface, Robin finds himself working together with the one person he never wanted to see again: Slade.

Without the Titans knowing, of course.

Notes:

Guess who’s making another apprentice fic! (I’m addicted.)

Like usual, this story takes place in the 2003 Teen Titans Animated Series. However, I tagged Young Justice because I made Robin’s past based on season one of the show.

Basically, this is an AU where YJ Season 1 Robin grows up to be 2003 TT Robin. It’s not THAT important, but does add a decent amount to the plot.

This fic also uses a work skin I made for Titan communicators whenever they chat, so I recommend you keep the style on!

Besides that, I hope you like it! ❤️

(See the end of the work for more notes and other works inspired by this one.)

Chapter 1: Compromised

Summary:

Robin gets hit with truth serum. He reveals things he would rather not.

Notes:

Please make sure you have Creator Style/Author Work Skins activated! And sorry if you're reading this on a pdf, the format might be weird.

(See the end of the chapter for more notes.)

Chapter Text

It was supposed to be a normal day of justice in Jump City—the usual routine.

The Titans would take down some petty villain, call the cops to arrest them, eat a large pizza to celebrate, and then go home and sleep.

After all, it was Jump City. Sure it had some crime, but compared to Gotham? It was nothing.

Robin had dealt with worse things before.

He had faced off against criminals, meta-humans, murderers, and other dangerous obstacles. He had developed gadgets, hacked motion sensors, and even dabbled in shady organizations and substance dealings that he probably shouldn’t have.

He was experienced. Knowledgeable. One of the best out there.

But due to this expectation—this belief that he had grown exponentially from his past—he must’ve grown soft.

Seriously.

Because how, how in the world, did his team end up separated?

Sure, the villain they were facing was some sort of unknown cult with around a hundred followers, and sure, they had high-quality tech on-hand that could somehow block their Titan communicators—

But still!

Five titans. Five amazing superheroes. And they couldn’t even stay connected?

The idea made Robin want to shake his head and dive headlong into training exercises. Teamwork was important, and he had learned that the hard way when he was thirteen, and once again with Slade as his former apprentice.

But as much as he wanted to criticize his team’s ability as a whole, Robin totally had the worst offense. Totally.

(God, was he growing soft. What was happening to him?)

He had been accessing his communicator, trying to regain contact with his team by whispering emergency codes, all while outrunning three hooded figures. He grumbled to himself, his mind furious by the fact that he couldn’t recognize who they were.

The Titans had been called to help stop them from stealing an important chip at S.T.A.R. Labs.

Robin would’ve thought the building had upgraded its security since the last time he had waltzed right in and stole something for Slade.

But no. Of course it was still susceptible to break-ins.

Robin scowled. Perhaps this city has also grown soft after having superheroes to rely on for too long…

Temporarily disabling his own firewalls to reopen a backdoor channel and regain communication, Robin reached for his bo staff and flung it at his pursuers.

His staff circled rapidly, quickly knocking out two of the three followers in its path with a rotation in the air.

While the two had fallen to the ground, Robin had also reached for a few birdarangs out of his utility belt, throwing it on the ground to stall the last pursuer as he ran further and further into the complicated back allies of Jump. He caught his bo staff returning back to him as small explosions began to go off.

The one follower remaining had coughed, his voice thundering and feet halting. “Don’t lose him! Get him!”

Robin’s brows furrowed, his voice still whispering codes. Noticing his device starting to work again, he hastily opened up the main communication channel.

“Titans! Do you hear me? It’s Robin, we need to regroup.”

Robin could only frown as he heard the sound of static reply back. When this was over, his team needed to create numerous back-up plans for when stuff like this happened.

(Damn. He still had a lot to learn. How would he ever catch up to Bruce?)

He fiddled with the communicator in one hand, pressing buttons on the touch-screen, while throwing smoke bombs with the other. With a smoke screen now created, Robin tried to find an opening to escape. Even if he was losing his touch, at least he was always good at concealing himself from others.

Using his senses, he silently darted towards an empty direction, his feet taking him down multiple paths and streets he had memorized diligently before. It was second-nature to him. Holding back the old urge to laugh at the confused thieves, he found his eyes focused on the Titan communicator instead. He tapped the buttons relentlessly. 

C’mon! Please work! Just let me reach anyone—

“Robin!” he heard someone yell through the device, the male voice frustrated and deep.

Robin’s eyes lit up instantly.

Finally!

“Cyborg! What’s the situation? I was being chased but lost the pursuers. I already contacted the police and connected them to my coordinates,” the teen stated as fast and clear as he could.

Robin heard a wave of static before Cyborg answered back.

“They got us good. Beast Boy is still outside the lab near the entrance, fighting who-knows how many people. I placed a tracker on the chip earlier, and now I’m going down to join him. This cult thing is huge! I don’t know where Raven is, but Starfire is in the air right now chasing the members and shooting starbolts. Look for green in the sky.”

“Got it,” Robin replied, his eyes quickly scanning his surroundings as he ran. He gripped his grappling hook, shooting it towards a building. As his feet left the ground, he continued to ask for more details. More information.

“Where’s the chip now? What does your tracker say?”

He rolled into a ball on the roof of a building, ensuring a safe landing. From the top, he could look down and see the whole city. He couldn’t see any remaining pursuers. At least, not yet.

Cyborg grunted, his voice fluctuating as he seemed to be blasting sonic cannons as he tried to make it down to Beast Boy. “From what I can see, it’s still there. In the lab.” The half-robot’s words paused, the sound of wind and rustling overtaking the audio reception.

Static continued to mix with the audio as Cyborg spoke. “—The members aren’t even going up there anymore. Using my heat scanners, all signs of warmth from a human being are going back downstairs to leave the building. No one is going after the chip anymore it seems. Sensors don’t detect any other non-human entity either.”

Robin’s eyes narrowed. “So it was a decoy? What do they really want?”

“Don’t— know—!” Cyborg slowly replied, his actions now preoccupied with fighting rather than communicating.

Robin exhaled a breath as he leaped from building to building. He was a hero! One with a lot of experience.

He could do this.

He could determine their motive.

(Batman would've done it by now. He would’ve already been finished for the day, handing the entire organization to the police with information on everyone. Gotham would’ve cheered and partied, while Robin would remain standing in his shadow. Again.)

The original purpose of the chip was so that it could bypass certain codes and install new firewalls without the original administrator noticing. It was a simple thing, but very powerful in the wrong hands.

But considering how the group had already managed to block their communicators, Robin should’ve known something was up. They wanted something else. But what?

In Jump City, there were only a few good targets for criminal activity: Wayne Enterprises, S.T.A.R. Labs, and Zynothium.

Luckily, Robin had already taken care of that last one, and Robin already knew too much about the first two. Both organizations had recalled significant top-secret experiments and innovations back to headquarters after Robin—against his will—had infiltrated both places in less than a week.

That only left one target, then.

The Teen Titans themselves.

His fists clenched as he realized that Raven was still missing.

Had they taken her? Was she the true mission after all? What did they want with her?

Trying to stay calm, he acted the way a perfect leader would. Something he had learned over the past few months.

No more going off by himself. No more separating hastily. No more feeding into his suspicions without proper evidence.

He would regroup first, and then continue on from there.

And so, Robin flew back to S.T.A.R. Labs.

Unfortunately though, that area was now infested with those unknown cult members. How great.

He turned on his device again. “Cyborg, I’m on my way to the lab. Tell Beast Boy. I’m coming up with a plan, but we all need to regroup.”

Robin winced mid-air as he noticed a group of shady people standing on a nearby roof. They seemed related to the organization they were against. Begrudgingly, it seemed he would have to return back to ground level for now. Memorizing and sending the address to the Titan files with the press of a button, Robin hastily jumped down onto a stairwell, moving his cape around to fit in the shadows.

After making sure he was in the clear, he darted off to Cyborg’s last reported location. Static came again, the sound emitting from the communicator as Cyborg tried to connect.

“Okay, I’ll tell the others. We’re facing around thirty people right now. Odds seem to be equal, and nobody is overpowering the other just yet. They have some pretty damn good tech though. Who dealt this stuff to them? Some of these things look new.”

The half-robot grunted, his voice tight as he added:

“Raven can barely keep up with her spells.”

Robin had to hold back the urge to pause and stop running, his fingers almost dropping the faulty communicator.

“I’m sorry, Raven is with you?”

Robin heard a cannon power up through the speaker.

“Yes-? She’s been here. For a while, actually.” Cyborg said. “She told us a good three minutes ago that she was making her way back on the main channel. Didn’t you hear?”

Robin’s eyes widened, his mask sticky with sweat. “What? I didn’t hear that. I’ve been on the channel the whole time, and I only heard you.”

Cyborg inhaled a breath sharply. “What? The communicators have been back on for the past five minutes. Do you not see our locations on the map?”

“No—I don’t see anything.”

“Well everyone else’s communicator is back on. Even Star, she’s been talking too, which means it’s only you that still—shoot.” Cyborg’s voice turned grim.

Robin felt a shiver go up his spine.

What?

His communicator was the only one still compromised. He was the only one who couldn’t reach the others. He was the one separated the most from the group. Just like before. Just like back then with Cinderblock. Which meant—

“—they’re after you, Robin!” Cyborg finished, his voice laced with concern. “Damn it, I’m sending Star to go after your coordinates right now. Can you hold on?”

Robin felt his throat dry. “I can. I can—I can hold on. I’m still on my way to you. I can meet her in the middle.” Beads of sweat started to roll down his forehead.

Now that he was aware of it—him being the true target—he found it harder to act normal. Harder to act casual.

And it didn’t help that Robin truly felt alone.

For someone who was being targeted and purposefully separated, it was odd how Robin couldn’t sense anyone nearby. He held onto his bo staff, ready to attack.

He felt like he was back in Gotham again.

Cyborg’s muffled voice rang through the faulty communicator, the audio fuzzy in Robin’s left hand.

“Star said she’s coming. Be careful, Robin!”

And that was the last thing Robin heard, before being left in silence.

Silence.

There were no distant sirens, no footfalls, and no echo of Starfire’s flight cutting through the air. It was all silent, as an unsettling hush echoed through the empty streets and occasional streetlights.

Robin bit his lip anxiously as he moved. 

It reminded him of the nights he had spent months ago, savoring the quiet of Jump, before Slade would remind him that it was time to return to his haunt.

It reminded him of what felt like a lifetime ago, when his old team, before the Titans, would sneak out at night to secretly fight crime in order to make a point.

It reminded him of how silent things got whenever the others weren't around—whenever he had decided to go off on his own again.

(When he started to act like Slade again.)

Robin slowed down uncomfortably, shuddering as the old memories he had shoved down began to resurface. What should have been a distant blur kept creeping back upward, the fingers of every image clawing at him slowly.

It seemed to be happening a lot lately—hesitating, making more mistakes, being soft and seeing things he shouldn’t. 

It was a weak point. Something he should have never entertained if he wanted to get better.

It was a vulnerability.

And what led up to his first mistake.

His instincts just narrowly recognized something was wrong as his boots touched the pavement, a hissing sound flying through the air.

A sudden jolt of pain burned the side of his neck.

“—Shoot!” Robin yelled, his cape flying as he spun out of the place he had just been standing.

(A useless maneuver now, showing how he really only had pure instinct left. Pathetic.)

His hand flew up to clamp over the sting just beneath his jaw. Panicked, but trying to maintain his thinking, he forced his fingers to examine. To extricate information on what the hell had just happened to his neck.

His hand pulled away from his neck, his fingers damp.

This wasn’t blood. This was too thin. Too slick.

His pulse spiked.

A syringe.

The hooded figure stood closer than Robin liked—closer than what should have been possible—gloved hand  retracting as Robin lashed out with his bo staff. The impact cracked hard against the attacker’s ribs, sending them back across the asphalt.

Robin didn’t move further. Instead, his grip tightened around his neck.

“No,” he muttered under his breath, his voice hitching despite his effort to control it. “No, no—what did you give me?”

He could feel his heartbeat racing helplessly as he tried to make sense of what was happening.

Damn it! How had he been so distracted that he hadn’t noticed? How had he been too slow to dodge or attack or do absolutely anything?! Hadn’t he learned by now to be faster? How to connect the dots quicker? How to just be smarter?

Losing his grip, his brain started to supply him unwelcoming visions. Visions of the past—the last time he had been hurt like this. The nights he had spent in Wayne Manor injured and bed-ridden. He remembered the casts, the quick fix-ups with Alfred, and the way Bruce had stared down at him concerned, yet also mad and ready to take him off-field forever.

He remembered a black and orange mask peering down at him on the floor, a single eye displaying heavy feelings of disappointment.

Dick didn’t want that to happen ever again. He just had to pray he would get out of this.

No, he would make sure he would get out of this.

Stay focused. He thought to himself. Find out what they injected you with, and don’t let them exploit it. Stay strong. You are Robin.

The feeling coursing through his body felt familiar. Uncomfortable, but familiar. As if he had gone against it before. He just needed to think.

The attacker quickly recovered, staggering upright. Then, a few others emerged from the shadows behind them. From what Robin could tell, there were about three more of them.

It was all so strange. He couldn’t recognize these people. Not their looks, clothing, patterns, behaviors—nothing. And yet, they were skilled. They moved deliberately and purposefully.

Just who were they?

Earlier, the pursuers had been rather messy, but this specific section of the group was good. This organization…it didn’t make sense. High tech, but chaotic operations. What was their motive?

Someone laughed.

“Don’t panic, Boy Wonder,” one of them taunted. “It’s already working.”

Robin’s head snapped up at that, his mind trying to hold onto that statement and dissect it.

His mind raced through several ideas—chemical profiles, delivery methods, counters. Tranquilizers didn’t feel like this though. Neurotoxins didn’t either. This was… warm. Crawling. Like something loosening inside his skull.

Hadn’t he felt this before?

An image of the Batcave came to mind, a vial of liquid in Batman’s hands—

Robin blinked.

He was right. It was familiar. More familiar than Robin would have liked. It was a substance that Robin had seen before in the past. Had trained with.

Truth serum.

The realization made his eyes widen, his breath hitching.

And like an idiot, he panicked.

“No,” the teen breathed, bewildered. His voice gained volume. “No way—!”

He ran forward in a blur of practiced motion—smoke bombs, birdarangs, a sweeping strike that knocked one pursuer off their feet and sent another crashing into a fire hydrant.

His body still obeyed him. Muscle memory was intact.

But his thoughts—his thoughts were slipping.

He hurriedly bit his lip, the action fierce enough to draw the taste of iron in his mouth. Focus. Don’t talk. Don’t answer. Don’t think out loud.

He jumped over a car, rolled, and came up on one knee. The world tilted to his eyes. His heart couldn’t seem to slow, and his breath was shallow.

He needed to remember what had happened the last time he had got the serum. What had he said? What did Batman tell him?

It was hard to recall, as clearly this dose was stronger. It had more power, his body still trembling from the injection.

Someone shouted from a distance. “Keep him talking!”

Robin grit his teeth.

“I don’t want that to happen!” he snapped automatically—and froze.

The words had come too easily.

“...Okay, maybe it’s working,” he admitted, before he pressed his hand to cover his mouth. Hard.

What in the world was he doing, acting like an amateur? Like a kid?

He kept running, his thoughts shooting off at a speed so fast that even KF would be surprised.

Shoot, what if they asked him for his identity? For Batman’s identity? Or his old team? Or literally anyone—ugh, why did Robin know so many secret identities?!

Robin clutched his staff, realizing that more and more waves of people kept coming. There was nowhere left to go. Not even a nearby sewer. They had gotten him good. Robin tried to steady his breathing as strangers circled him from all sides.

“What’s the name of the person who trained you?” one of them called, his hand now brandishing a knife as he approached the teen closer.

Don’t speak. Don’t think. Don’t—

Robin laughed without meaning to. A familiar, old cackle he thought he couldn’t even make anymore. The sound startled him more than it did them.

“That’s classified,” he said automatically, his past training finally deciding to kick in.

Then—against his will—

“But I guess I can tell you about Slade, he did a lot of damage to me when I was his—” his mouth snapped shut, biting his tongue in pure anger.

What was he saying?

He didn’t say Bruce, which was good, but he had also admitted that Slade did in fact train him, and had given him some good pointers while also hurting him to the point where he had bled and bruised and cried and—

A memory invaded his mind.

He had been in a getaway car—his clothes stained orange, black, and red—as Slade’s singular eye peered into his skull. 

“I won’t allow my apprentice to break.”   

Robin briefly shut his eyes, struggling to regain his composure. 

Stop. Don’t think about it anymore. Don’t think about him anymore! Fight back! Resist!

Back in the present, his body moved again, bo staff slamming against concrete as he fought another opponent. But his mouth kept threatening to betray him—truth clawing at his tongue and demanding release. He knocked the knife out of a man’s hand, before backing away, chest heaving. He raised his staff up once again. 

“Stay away!” he barked, his voice shaking. It wasn't with fear, but with effort. More than Robin would have liked. He grit his teeth. “You don’t want what happens if I keep talking.”

Something inside him wanted to talk.

Wanted to confess. Explain. Strip the armor away piece by piece.

Talk about the things he had endured. Reveal the guns he had fired—
The blood on his hands from what Slade had told him to do.

‘Robin, what happened to you?’ he heard himself think weakly, even though he already knew the answer.

After all, he had been broken for a while now.
And it was all Slade's fault.

A man scowled, his footsteps inching closer to Robin. “I know what I’m getting into, kid.” His voice was rough, the tone laced in frustration.

However, Robin heard something change in the man’s voice as he spoke once more.

“Hey, I have a good question!” The attacker laughed.

“What happened to the other Robin in Gotham?”

Robin felt his chest still, his breath stopping entirely. He felt as if the world had shifted, knocking air out of his lungs. He clenched his staff harder, anger starting to pour onto his features. How could they—how could they even ask that?!

It was sickening.

He felt the serum flowing in his body—the substance alive. His mouth wanted to answer, but his body felt numb. The words were starting to form, but his mind was just so angry.

Then, in the midst of his turmoil, a shadow loomed overhead, covering the ground where he stood.

“Robin!”

And it was green.

The teen couldn’t hold back a smile as he saw her.

The green light flooded the street as Starfire descended like a comet, starbolts flaring. The remaining figures were blasted backward instantly, skidding unconscious into a heap of rubble. The last one turned to flee, but was pinned to the ground by Robin’s staff, thrown with brutal precision, and ended up unconscious.

Starfire landed beside Robin in a rush, hands already reaching for him. “Friend Robin! Are you injured? Your pulse is—!”

Robin raised his hand, a ‘stop’ motion made with his palm. Starfire’s heart rate was going a mile a minute, as she had clearly rushed to get here on time. As a good leader, he needed to reassure her. He needed to alert his team that he was okay. His mouth desperately tried to claw out the words: I’m fine.

But of course, that’s not how a truth serum works.

No, it doesn’t let him spout lies.

No matter how much he himself believed in them.

“I’m not fine,” his voice stated, his eyes widening in shock as he realized what he had just said. “Oh no.”

Starfire looked even worse now, her eyes wide and her hands quivering as she spoke.

“What?! Do you need assistance? A hospital? Robin, do not die on me—I can not lose a friend!”

Robin quickly shook his head, his hands waving adamantly. “I’m not dying Star! I’m just…” he sighed, words spilling before he could contain it.

“Not feeling the aster.”

He winced.

Starfire opened her mouth in concern. “What? What does that mean—”

“Disaster without the prefix,” he heard his voice say against his will. “A word I used to say. It…means the opposite of disaster.” Robin explained, his face turning pink.

Genuinely, what was happening to him? He hadn’t said that word in years.

He coughed into his fist, embarrassed. He looked up at Star, his eyes full of intent. He needed to pull himself together.

For Starfire.

For his team.

“I got hit with truth serum,” he admitted. “Makes me say the truth whenever I’m provoked. I can fight it off, but not for long. And it’s been awhile since I’ve been exposed to something like this, so my resistance might be worse than it should be despite my training.”

Clearly.

It was one thing to reveal his old, trivial speaking habits from when he was thirteen.

It was a completely other thing to reveal his old apprenticeship with Slade—something that no one should ever, ever know.

Even Batman didn't know. Robin made sure of that.

Starfire’s eyes widened at the explanation of the serum, before nodding hesitantly. “So…you are the fine physically, but not in your head?”

Robin scratched the back of his head. “I…I guess so? I don’t really know as of now,” he frowned, disgruntled by how strangely talkative he got in this state.

He lowered his voice to a whisper, aware that other people could still be around as blue and red lights started to show up, the sirens emanating throughout the street.

“You can’t ask me anything, Star. There are things I can and cannot say. Don’t let them hear me. Don’t let the others—”

“Robin,” Starfire said firmly, her hand now holding onto his. She squeezed it. “You are safe now. I will protect you. I promise.”

Seeing her pure determinism, he laughed, his face breaking into a smile.

Starfire, taken aback but pleased by the rare show of emotion, returned a smile back.

And somewhere, deep inside Robin’s mind, something carefully buried was already beginning to claw its way to the surface.

And as the boy found himself whispering “he’s gone” under his breath—a delayed answer to an earlier question—

Robin didn’t know how long he could keep it all in.

Notes:

I love Dick Grayson truth serum fics, and I think adding the apprenticeship arc to the concept really makes it interesting!! Especially since it’s post-apprenticeship too. I’m so excited to write more of this!

Also, I find it worth mentioning that this fic takes place after my other apprenticeship fic, Trigger (part one of this series). You don’t need to read it to understand this one, but don’t be surprised if you see some references to it throughout.

Slade really impacted Robin didn’t he…I would say poor guy but I’m really all for it lol 🖤🧡

The plot really thickens later on, so I hope you stick around for it! Slade becomes DEEPLY involved. Thanks for reading! :D