Actions

Work Header

Rating:
Archive Warning:
Categories:
Fandom:
Relationships:
Characters:
Additional Tags:
Language:
English
Series:
Part 3 of TFiTP (The Flaw in the Plan Series)
Stats:
Published:
2026-01-05
Updated:
2026-03-09
Words:
27,250
Chapters:
9/34
Comments:
124
Kudos:
75
Bookmarks:
19
Hits:
1,801

The Flaw in the Plan - Book 3

Summary:

In which an escapee learns that Harry Potter is the son he never had, a Defense Professor grows closer with his pupil, a certain Potions Master becomes more than a Professor, and two boys learn that things aren't so bad once they're together.

This covers Prisoner of Azkaban, and is Book 3 in the Flaw in the Plan Series.

Chapter 1: Wisteria Walk

Summary:

Harry's calm summer takes an unexpected turn.

Notes:

we are back. WITH BOOK 3!!!!

are you hype? CUZ I AMMM I have been hype for everything but specifically book 3! so much I've been holding back... AYAYAY IM JUST SO EXCITED !!

this book is shaping up to be longer than both the first + second combined, which doesn't surprise me. but what IS surprising me is how long this outline is taking 😭 i spent 4 hours on TWO chapters the other day and that was just the outline. so bear with me when I say: I will get it done. No, I will not pause updates. I'm up to chapter 20 right now, but I don't have a concrete number yet.... just that by ch20, we're still only halfway through my plot lmao. So there won't be an official chapter count for a while.

so buckle up kids!

and mind the tags. I'm not lying when I say there will be graphic depictions of CSA. It's necessary for the plot-- I don’t like dwelling on the gross stuff on purpose. But they are fleeting-- no entite chapter will be a depiction, only bits and pieces of entire chapters but I will always warn you guys in these notes. You can always skip those things if it makes you uncomfortable, you're never obligated to read them 💙 so please know your boundaries and stay safe!!

and finally, as is typical TFitP fashion, we will be starting this book off with some abuse. TW FOR EXTREME HOMOPHOBIA, F-SLUR, AND MARGE

and with that all out of the way, enjoy! 😋

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

Chapter Text

Harry Potter felt very certain he was correct in saying that he was, for the very first time, excited for his birthday.

 

This year was different. This year, he would not be spending his birthday in his cupboard, or tracing a birthday cake into dust. This year, he had friends.

 

And friends, Harry knew, meant gifts.

 

Though he was also nervous. He didn't doubt that his friends knew him very well, it was just– well, what if something went wrong? Harry was no stranger to being let down, so much so that he'd grown accustomed to it; he expected it. But this year was different, and this year, he was afraid.

 

His summer had gone decently so far– he had returned to Privet Drive to find the bars on his windows removed and a vague order from Uncle Vernon to ‘stay out of our way, boy.’ He'd spent June, and now almost the entirety of July, in his room and up and down the lane, venturing around Wisteria Walk, well out of the Dursleys’ way. Harry didn't know the full extent of what Narcissa had done to them last year, but it had been enough to traumatize them and keep them traumatized throughout Harry's annual stay. He'd only been yelled at three times: once for burning the bacon, twice because Hedwig had been making a racket (she was no longer confined to her cage, but Harry wasn't allowed to open his window), and thrice because Uncle Vernon's football team had lost and he'd just felt like it. No beatings, no extreme starvation. . . part of Harry thought they were holding off because they had something much worse for him in store for the rest of his summer. The other part was hopeful he would finally have a normal, not eventful, almost boring, summer.

 

Later on, Harry thought he ought to have learned better by now.

 

The Sunday before the beginning of the week of Harry's thirteenth birthday, Harry was serving the Dursleys dinner as usual. He was just plating Uncle Vernon's large serving of bangers and mash when he heard his Uncle say something that made his heart stop. 

 

“Of course, the boy'll do all the cleaning and preparing for Marge's stay, that way he'll be good for something–”

 

The plate in Harry's hands clattered onto the table in front of Uncle Vernon, splashing gravy all over the wooden finish. 

 

“What the hell is your problem, boy?!” snapped Uncle Vernon, but Harry ignored the mess.

 

“Marge is coming?” asked Harry, fear lacing his words. “She's– she'll be staying here?”

 

“For a week!” said Uncle Vernon, glaring at Harry suspiciously. “What's it to you, boy? You heard me! You'll get to all the cleaning and hoovering and dusting and straightening before Marge arrives tomorrow–”

 

Harry paled. “Tomorrow?”

 

Uncle Vernon's face was rapidly reddening. “Are you deaf, boy? You'll start it all tonight! I want my house spotless! And you'd better be grateful to Marge, it's not her fault what happened to a freak like you! You'll act properly and respectfully or you'll get the stuffing beat out of you!”

 

Uncle Vernon was yelling now. Harry felt nauseous, what little food he'd eaten churning uncomfortably in his stomach. Anger boiled underneath his skin. Aunt Petunia had her eyes trained on her plate, pushing her mash around with her fork. Dudley's five chins were wobbling as he ate and ignored everyone around him, laughing at something on the Telly.

 

“Yes, Uncle Vernon,” whispered Harry. Typically, his Uncle would shout for him to speak up, but even he looked slightly uncomfortable. He waved Harry away and Harry hurried to the cupboard, collecting the cleaning supplies without looking around at the tiny, stained mattress or the drawing tacked on the wall. Peter and Me. Harry closed and latched the cupboard before heading upstairs to begin the daunting cleaning that awaited him.

 

He thought he ought to have known better by now, than to have hope for an uneventful summer. With Marge came unpleasant memories; Harry would just have to stay out of her way and fight the tide.

 

~~~~~

 

The next morning, Harry was woken by knuckles rapping on his door. Aunt Petunia hollered for him to finish the cleaning before she clattered back downstairs, in her tacky heels Harry knew she saved for special occasions. Harry rubbed his face and stretched, his back popping and aching from the excess labour he'd performed the night before.

 

He'd hoovered, organized, and disinfected the entire kitchen and dining area. He'd done the same to the living room and hall, and had washed all the linens by hand as was his usual chore. He'd prepped the guest room and bathroom, scrubbing the tile on palms and knees, doing the corners with a toothbrush the way Aunt Petunia liked. He'd gone to bed at around four in the morning, and he still had to maintain the garden, wash Uncle Vernon's car before he went to pick up Marge from the aeroport, hoover the upstairs hall, and make himself as presentable as possible, which meant tackling his unruly hair. Harry was not looking forward to that last part– it was an impossible task, and the unrulier he was, the happier Marge would be.

 

Harry got up and dressed quickly, explaining to Leto and Hedwig what was happening. He had only a few hours to get everything done, so he needed to begin immediately. 

 

By the time Marge arrived, Harry had done everything except make himself look presentable. When Uncle Vernon returned with Marge and Ripper, Harry was still wearing his cast-offs, instead of some of the nicer clothes he'd owl-ordered with Draco's help all that time ago. Some of them still fit, but Harry had donned a pair of Dudley's old jeans that were about a foot too long and three too wide and an old raggedy sweatshirt twice as big as he was for the cleaning. When Marge slapped a crisp, twenty pound note in Dudley's meaty hand and bumped jaws with Aunt Petunia, she rounded on Harry.

 

“So!” she said, glaring down at Harry. Her resemblance to Uncle Vernon truly was uncanny– she was very large, with very little neck. She did not have a mustache, but her nose was so large it cast a shadow resembling one above her upper lip. “You're still here, are you?”

 

“Yes,” said Harry as politely as he could manage.

 

“Don't say ‘yes’ in that ungrateful tone,” snapped Marge, “if it were me who'd wound up with you on my doorstep, I'd have sent you straight to the orphanage, it'd have straightened you out!”

 

With that, Marge tossed her things at Harry as if he were a coatstand and bustled into the kitchen, where Aunt Petunia was preparing breakfast. 

 

Harry brought Marge's things upstairs and into the guest room before heading back to his own room and shutting the door, sighing.

 

It was going to be a long week.

 

~~~~~

 

Harry managed to stay out of the Dursleys’ way, for the most part.

 

He occupied himself with his typical chores, which were of course neverending. The constant scrubbing, hoovering, and organizing kept his mind off the more unpleasant memories he associated with Marge.

 

Marge was a loud houseguest. She spent most of her time sat in front of the Telly, watching whatever sappy romcom was on, or the news, and making horrible comments about it all. She constantly sang Dudley's praises, saying he was a pleasant, well-fed boy who had turned out a lot better than ‘that Potter brat. At least Dudders has got some meat on his bones.’ When Harry was around, it worsened.

 

Tuesday afternoon, Harry was coming inside from the garden, tanned and sweaty from weeding the begonias. He'd let Leto out to hunt rats and other vermin to share with Hedwig while he worked, and the snake was dozing contentedly around Harry's waist.

 

Unfortunately for Harry, Marge had been coming down the stairs just as Harry made past his cupboard.

 

She'd glared at Harry, eyeing him up and down. For a startling moment, Harry thought she could see Leto through his sweat-stained clothes. 

 

“So,” began Marge, “you still strut like a girl! I thought Vernon squashed that out of you years ago. . . maybe he'll need to do some extra work.” Marge had smirked then as Harry felt something hot and heavy settle in his stomach.

 

“I don't know what you mean,” said Harry quietly, not meeting Marge's eye.

 

Marge had barked out a laugh. “You still talk like one, too! How my brother stands you, I don't know, boy. . . you're lucky he and Petunia kept you and fed and clothed you. If it had been up to me, I'd have given your food to the dogs.”

 

Harry had darted up to his room, face and eyes burning.

 

All week, life for Harry at Privet Drive gradually worsened until finally, that fateful dinner on Friday, the day before Harry's birthday.

 

Aunt Petunia had pulled out all the stops for Marge's departure meal. In fact, Harry hadn't seen her cook so much since before he was old enough to reach the stove and cook everything himself. Aunt Petunia did the cooking every then and now, but Harry was the one who did it most often, especially for large feasts such as this and the one with the Masons the summer previous. 

 

Harry served the Dursleys an entire Sunday roast, complete with roast lamb, boiled potatoes, Yorkshire pudding, cabbage, carrots, parsnips, and peas. He bustled around the table, divvying up large portions of everything to Uncle Vernon, Marge, and Dudley, and smaller portions to Aunt Petunia and Ripper. Harry contented himself with the leftovers in the kitchen, finishing a potato and an entire lamb chop. It was more than he'd eaten in days, so he paced himself whilst listening to the conversation drifting in from the dining room.

 

“Excellent nosh, Petunia,” said Marge, her words slurring. She'd had quite a few glasses already, and was becoming tipsier and tipsier. “This lamb would go excellent with some scotch. . . don't be shy, Vernon. . . not yet, not yet– that's the ticket!”

 

Harry heard the sound of sipping and then a loud, contented belch.

 

“Very good,” said Marge, burping again. “Look at my Dudley! Eat up, lad, a good boy like you needs proper feeding.”

 

“Thank you, Aunt Marge,” came Dudley's smarmy, falsely-sweet voice.

 

“You know, Vernon,” said Marge, “don't blame yourself for how that other boy's turned out. You've done all you can, there's not much more you can do if there's something on the inside.” Marge paused, and Harry assumed she was taking another drink of her scotch. “You see it all the time with dogs. If there's something wrong with the bitch, there'll be something wrong with the pup–”

 

The anger that had constantly been boiling under Harry's skin crested over for a moment before Harry quickly shoved it back down. Though it was in vain; the tide had not receded quick enough. From the dining area came the sound of glass breaking, and then much sputtering and confusion.

 

Harry gripped the counter, his knuckles whitening as he fought to keep his emotions under control.

 

“Marge!” squealed Aunt Petunia, “Marge, are you alright?!”

 

“Not to worry!” said Marge, “I have a very strong grip. . . where's that boy, to clean this up. . . brat!”

 

Harry took a steadying breath and schooled his expression before wiping his hands and stepping into the dining room. “Yes, Aunt Marge?”

 

“Come clean this up,” she said, snapping her fingers and gesturing around herself. Shards of glass had flown in every direction and were scattered all over the table and floor. Marge's ruddy red face was dripping with scotch. “And get me a new glass.”

 

“Yes, Aunt Marge,” said Harry flatly. He returned to the kitchen, grabbed a cloth, and headed back out into the fray just as Marge started speaking again.

 

“Say, whatever happened with that doctor I recommended he,” she gesticulated at Harry, who was numbly cleaning the glass from the table, “go see all those years ago? At St Brutus’?”

 

Everyone at the table, including Harry, froze. Harry heard the sounds of distant water roaring in his ears. 

 

Aunt Petunia's mouth opened and closed a few times before she answered.

 

“Oh, you know,” said Aunt Petunia, laughing awkwardly, “we had Harry see him for six out of the eight months, but. . .” Aunt Petunia's face went green, her mouth drooping. “It was costing us too much, so we stopped.”

 

It was a lie. A bald-faced lie, and Harry knew Uncle Vernon and Dudley were aware it was a lie, too. But neither of them said anything.

 

“Shame,” belched Marge, “Though, I would happily pay for him to go back. I mean, I'm sure I told you about my friend whose brother was experiencing similar issues, and he had good results. I even heard that they have new doctors now, that specialize specifically in treating cases of homosexual behaviour–”

 

Another glass, Aunt Petunia's this time, shattered, though Harry did not move to clear away the glass. Uncle Vernon glared at Harry, and Aunt Petunia stared at him, her expression fearful, and almost. . . guilty?

 

But Harry's mind was racing too fast to properly place it. All the unpleasant memories Marge's presence aroused were now free from the depths of Harry’s mind, flashing to the front of his conscience, projecting in front of his very eyes–

 

The arched sign over the entrance's large, dismal double doors. . . St Brutus’ Hospital for Incurably Criminal Boys. . . the long, sterile hallways. . . other Brahms Boys with hollow eyes. . . his office, sterile and medical and bright, and the doctorate on the wall with the loopy signatures, the one Harry used to stare at while–

 

“Of course, those things can never be completely stamped out in only six months,” continued Marge. Her voice sounded muffled and strange, as if Harry were listening from underwater. “Perhaps sending the boy back will do him some good. . . fault of the parents, of course, that stuff is in the genes, and wishy washy folk tend to support those kinds of tendencies. What was the doctors’ name again?” Marge belched. Harry felt his control slipping. “A weird one. Evansir. . . Brahms, was it?”

 

Doctor Brahms, with his shiny, shiny shoes and perfect pressed shirts and shiny, shiny smile. The doctor's hands were in Harry's hair, in his mouth, covering his eyes, inside him, all over him–

 

“SHUT UP!” yelled Harry, throwing the cloth full of glass to the floor. “JUST SHUT UP!”

 

Everyone at the table jumped. Harry felt shame and disgust and bile rising in his throat, the ocean roaring in his ears–

 

“You should be grateful to me, you little faggot!” yelled Marge, face red and livid. “I–” 

 

But Marge didn't finish. She seemed to be expanding, her body inflating like an overlarge balloon. The buttons on her dress, already stretched to their limits, popped and flew everywhere– one hit Dudley square in the forehead, another flew and hit the wall– 

 

“MARGE!” screamed Uncle Vernon and Aunt Petunia, jumping up out of their seats as Marge began to float, bumping the ceiling and bouncing off it.

 

Harry's breath was coming in quick, short jabs. His heart hammering against his ribs– Dudley was staring at him, genuinely shocked and afraid, as if Harry would blow him up next– Harry remembered a time when he himself would stare at Dudley with that exact expression on his face, and how he'd never, not until the very end, looked at the doctor that way, and how he should've. From the very beginning, he should've.

 

Ripper was barking madly. Harry ran from the dining area and tore upstairs, grabbing his rucksack and shoving his things inside it madly.

 

“Harry? Harry? What's wrong, what's happening?” hissed Leto from Hedwig's cage, where the two of them were sharing what was left of the rats.

 

“We're leaving,” hissed Harry, “I've had enough.”

 

Leto hissed worriedly, asking something else, but Harry couldn't hear it over the roaring in his ears. He went around his room for the last time, checking his nightstand and loose floorboard for any stray belongings. This was the room he'd almost died in last summer, starving and pissing in bottles, lying in agony with his back torn apart and bleeding at the hand of his Uncle. Harry felt the scars from that whipping tighten and flex on his back, like waxy inkstains he would never be able to erase as he donned his rucksack, grabbed Hedwig's cage, and bolted back downstairs, stopping in front of his cupboard.

 

Harry heard thundering footsteps headed in his direction as the cupboard door burst open due to his hectic magic.

 

“WHERE DO YOU THINK YOU'RE GOING, BOY?!” roared Uncle Vernon as Harry heaved his trunk and his broom from the cupboard. “YOU COME BACK AND YOU PUT HER RIGHT, YOU–”

 

In seconds, Harry had his wand out of his trunk and aimed at Uncle Vernon, who had a hand outstretched.

 

“I've had enough,” said Harry, breathing hard, “of you sick people– the number of times I've nearly died in this house because of you– you won't rule my life ever again. I'm leaving, and I'm not coming back.”

 

Pushing past a startled and shocked Uncle Vernon, the hairs on the back of Harry's neck rose as if sensing an attack– his back was to his Uncle, after all– but nothing came, and Harry kicked open the door and dragged his trunk up the lawn, past the garden he'd labored at for as long as he could remember, past the shed he'd once slept in, in the dead of winter, away from the house he'd spent his entire life at, being starved and whipped and hunted, and up the street, up Wisteria Walk, away from the Dursleys, away from the life of pain he'd always known, and into the dead of night.

 

~~~~~

 

“If there's something wrong with the bitch, there'll be something wrong with the pup–”

 

Harry grit his teeth and pushed on, ignoring the aching in his arms from dragging his heavy school trunk up Wisteria. The hand holding his broom and Hedwig's cage was sweaty, the wood of his Nimbus slick within his palm. The straps of his rucksack dug into his shoulders. 

 

"Oh, you know. . . we had Harry see him for six out of the eight months, but. . . It was costing us too much, so we stopped.”

 

Harry gave his trunk a sharp tug as he felt it catch on some pebbles free from the asphalt. Hegwig twittered in her cage, but Leto remained silent, wrapped around one of the bars and staring up at Harry worriedly.

 

“Perhaps sending the boy back will do him some good. . . fault of the parents, of course, that stuff is in the genes, and wishy washy folk tend to support those kinds of tendencies. What was that doctors’ name again?”

 

“No,” whispered Harry, giving his trunk another tug as he felt it catch on more pebbles.

 

“A weird one. Evansir. . . Brahms, was it?”

 

“No!” Harry gave his trunk the mightiest tug yet, and he lost his grip, the trunk skidding over the asphalt and hitting a curb a couple feet away. 

 

Harry dropped his broom and Hedwig's cage on top of the trunk, sitting down on the curb and burying his head in his hands. 

 

He'd left the Dursleys. Left behind years of torment and hardship, finally. 

 

Then, it hit Harry. He'd left the Dursleys. What the hell was he going to do now?

 

A ball of guilt settled in Harry's abdomen. He'd also abandoned his mother's protection, sanctuary she'd given her life for. Though the protection had never kept him safe from anyone inside that house, and he couldn't go back even if he wanted (which he didn't). Besides, thought Harry, I don't think of that place as home. A piece of his mother's protection would still live inside him; nothing could change that. Voldemort would never be able to touch Harry for as long as he lived.

 

Though Voldemort wasn't the only danger to Harry. He quickly took in his surroundings– who knew what dangerous criminals and hooligans could be lurking about? The curb he was sitting on was part of a sidewalk that led to an old, vandalized playground. Across from Harry was the shadowy alleyway between two buildings. He'd never been this far up Wisteria Walk before, in his earlier summertime wanderings.

 

Harry thought about the other place he'd grown to call home. Malfoy Manor, the vast, magnificent home of his best friend, the safe haven he'd been banned from only a couple months ago. Harry missed Draco very much, and, twistedly, wished he and his mother would come to rescue him from his predicament again. Though Harry was all on his own, and he mentally slapped himself for thinking so selfishly. Draco and Narcissa couldn't always be there to save him. The ball of guilt in Harry's abdomen grew as he thought of Draco's breakdown at the end of their second year at Hogwarts. How could he be so selfish, wishing for Draco to come and rescue him now, when Harry knew his best friend had more than enough weight to carry? Stupid, stupid. . . Harry gazed into the alleyway across from him. Stupid, stupid. . .

 

The shadows within the alleyway seemed to be shifting. Harry sat up, more alert, as the shadows actually danced and moved, taking shape. . . Harry squinted in the moonlight.

 

“Hello?” he said tentatively, slowly reaching for his pocket, where his wand was stored. He'd done plenty of underage magic already, surely a little more in the name of self defense wouldn't matter. But as Harry's fingers wrapped around the narrow stick of wood, the shadows came forward, and Harry made out the outline of a big, shaggy black dog, grey eyes glinting in the moon's light.

 

Harry felt his blood run cold. He'd just spent an entire week with Ripper, and this dog looked quite similar to the brute. Harry was not overly fond of dogs at the moment. . . he quickly got to his feet, raising his wand, when–

 

Crack!

 

The sound of Apparition split the night, and Harry jumped, tripping backwards over the curb and landing hard on the sidewalk. His rucksack cushioned the worst of the fall. “What the–” Harry looked around himself wildly. His eyes widened.

 

The looming, familiar shape of one very annoyed Severus Snape appeared standing over Harry. Harry stared at his Professor for longer than was appropriate, opening and closing his mouth uselessly.

 

“What on earth are you doing outside of the wards, on the ground, in the dead of night?” asked Snape incredulously.

 

Harry glanced across the street into the alleyway. The black dog was gone. 

 

“Potter,” snapped Snape. Harry's head whipped back to attention. “What are you doing this far from your Aunt and Uncle's house? Why did you leave the wards?”

 

Harry again felt quite cold. He became overly conscious of himself, sat on the sidewalk in his ratty trainers and worn green sweatshirt, rucksack twisted on his back, trunk, broom, and familiars all lying a few feet away in an unceremonious heap. His face burned, but the cold taking over his body made it so without the heat.

 

“Of course, those things can never be completely stamped out in only six months. Perhaps sending the boy back will do him some good. . .”

 

“I'm not going back,” said Harry, his voice broken and shaking.

 

Snape's dark eyes widened momentarily. Harry watched as his Professor's gaze swept over Harry, his belongings, and their surroundings.

 

Snape sighed heavily, closing his eyes for a few moments before opening them again. 

 

“You can come with me,” said Snape, a bit reluctantly, as if he hadn't expected to have an almost-teenager foisted upon him on a random Friday. “You can stay the night with me, and in the morning, we'll. . . we'll sort things out.”

 

Harry hesitated. He. . . he trusted Snape, but Snape was still a grown man who could take advantage of Harry if he wanted. Though a small voice in Harry's head argued that Snape had had plenty of chances to take advantage of Harry over the past two years, and yet he hadn't. 

 

“I swear to you, Potter, that you may come to me for anything. You don't need to explain yourself, I just hope you recognize that you can find solace in me, and that I have no evil intent. I swear this to you, Potter.”

 

“Potter?” prodded Snape, and Harry became aware that he had been staring at the man's face and gnawing on his bottom lip for the past thirty seconds.

 

Making up his mind, Harry stood, walking over to his belongings and made sure his hand was in contact with each item. He looked back at Snape, who was watching him sharply. Harry held out his hand.

 

Snape gave a curt nod before taking Harry's hand in his own and Disapparating them from Wisteria Walk. 

 

 

 

Notes:

next week: Harry gets acclimated to Spinners' end. He and Snape talk.

Here's my tumblr for more of my shenanigans...

Did you catch all of my double meanings? ;)

See you next Monday! 💙🫶🏿