Platform nine and three-quarters was churning like an ocean when the Potters arrived, waves of children crashing against the crimson doors of the Hogwarts Express with their trunks, cages, and homemade lunches pressed into their hands by harried mothers. Harry checked his watch as they hurried along the platform. "Only ten minutes," he called over his shoulder.

"Here's as good as anywhere," said Ginny, her hat slightly askew. "James, don't forget to ice your knee after Quidditch practices, and be sure to ask Madame Casfrey for liniment if you run out."

"I'll be fine, Mum," James sighed, already looking past her to the train.

"Lily," Ginny said, holding out her hand expectantly.

Lily groaned and begrudgingly handed over her smartphone. "Fine," she grumbled.

"I don't see why you'd want it at Hogwarts anyway," Ginny said, slipping it into her handbag. "Technology doesn't work well around magic, remember?"

Lily muttered something under her breath and folded her arms.

Ginny bent down and caressed Albus' face. "You'll hit your stride this year," she said encouragingly. "Things always settle down by fourth year."

"Unless you're Dad," Lily piped up.

"Hush," Ginny said to her sharply, then turned back to Albus. "Chin up, Albie. You'll be alright."

Albus looked a little pale, but nodded bravely and blanched when his mother kissed his forehead. "Mum, not here," he groaned, embarrassed.

Ginny kissed Lily and James too, then took Harry's hands in her own. "I hope you know what you're doing," she said.

"When have I ever?" Harry teased.

Ginny didn't laugh and he quickly grew somber. "Sorry, bad joke."

The train whistle blew suddenly, so Ginny kissed him and squeezed his hands one last time before stepping back from the train. "Stay safe, all of you," she called. "I love you."

"Love you too," Harry called back. "Come on, up we go."

They all boarded the train and Harry made to follow his children down the left-hand corridor, but Lily gave him an embarrassed look and he remembered that he was a teacher now, not just a parent accompanying his children, so he veered off down the right-hand corridor instead, ducking his head low as he passed cabins brimming with students. He found a quieter cabin in the rear section and quickly darted in, bolting the door behind him.

"Smart move, that."

Harry turned and saw a spindly man observing him from a window seat. He had reddish brown hair sticking out from under a pointed cap, and small brown eyes that blinked at him nervously. He was wearing a dark blue pullover and brown trousers, and in his lap he clasped a small briefcase with both hands. "Are you a new professor?" he inquired.

"Erm, yes, actually," Harry said, almost forgetting he was undercover. "I'm filling in for Madame Chase while she's away."

Harry stowed his trunk in the above compartment and sat opposite. "You as well?"

The man nodded. "Abbott Tamby, Defense Against the Dark Arts," he said, extending his hand. "And you are?"

"Harry Potter."

Tamby seemed taken aback and almost pulled his hand away, but Harry gave it a firm shake. "Weren't you working at the Ministry of Magic?" Tamby asked.

"I'm taking a sabbatical," Harry replied. "Professor McGonagall asked me as a favor, just until things are more settled. She's an old friend."

Tamby narrowed his eyes, but said nothing.

The train sped down the track at a cheery rate, and Harry found himself lost in memories of his own school years. He remembered sharing a mountain of treats with Ron that first year, and the wrinkle of disgust Hermione gave them when she barged in, looking for… what had she been looking for?

He thought of the dementors in his third year, and with a pang remembered how Lupin had so confidently driven them away with the first Patronus Charm any of them had ever seen. Lupin had been such a tangible connection to Harry's parents, the first person Harry had met that seemed to have truly known James and Lily Potter. Even now, decades after Lupin's death, Harry felt tears sting his eyes and he let the memory fade before they could fall.

He remembered being petrified by Malfoy in his fifth year and left on the train, only to be found by Tonks just in time. He remembered countless tense discussions as he, Ron and Hermione attempted to solve one conundrum after another, always on guard against Voldemort and his followers. It was hard to remember times on that train that weren't fraught with danger and anxiety.

"Mr. Potter?"

Harry emerged from his musings and met Tamby's gaze. "Sorry, what?"

"I asked if you were alright," Tamby said, frowning. "You seem preoccupied."

"I'm fine, thanks," Harry assured him.

The rode the rest of the way in silence, until the lanterns flicked on and it was time to change. Harry's school robes were black, edged with white like a referee's uniform, but as he slipped them on over his travel suit he felt utterly ridiculous. It's like wearing a bloody tent, he thought dismally. He hadn't worn one of these wretched things since he was a student, and now he remembered why as he fidgeted with the voluminous folds. Call me a Muggle, but what's wrong with just a suit?

The train platform below Hogwarts was tumultuous as students scurried back and forth and porters waved trunks off the train with their wands. "Gangway!" yelled a boy, skirting past Harry with a large cage. "Oi, all owls go on this cart!" called a porter, darting after the boy.

Just as Harry realized he didn't know where to go, a gaggle of first years wriggled up to the front of the crowd and stopped before a familiar figure waving a lantern. "First years this way!" he called, waving his lantern in a wide arc.

Harry's heart leapt and he squeezed through the crowd up to the front. "Hagrid!" he called.

The lantern stopped, its light catching the weathered face of Rubeus Hagrid. His beard was gray and his eyes squinted hard through the darkness, but once he recognized Harry he lit up like a sparkler. " 'Arry!" he beamed, nearly bowling over the first years to embrace him. "Professor McGonagall told me yeh were comin' on, fer the-"

"Teaching position, yeah," Harry interrupted, eyeing the first years. Hagrid turned to the students, nearly knocking his lantern into Harry's head in the process, and boomed, "This 'ere is 'Arry Potter, the Boy Who Lived!"

The first years oohed and Harry's face reddened. "I haven't been a boy in decades," he joked. "I'm just a regular teacher now, until Madame Chase is recovered."

"Ain't nothin' regular 'bout you!" Hagrid exclaimed. "What 'bout the basilisk, or competin' in the-"

The train whistle blew and Harry pounced on the interruption. "Shouldn't you be getting to the boats?" he asked.

"Blimey, so we should," Hagrid gasped, looking at his massive pocket watch. "Follow me, first years!"

The first years scuttled away after Hagrid and Harry caught sight of the thestral carriages being loaded. The spectral horse-like creatures used to disturb him, but now he found them as harmless as any ordinary animal. He climbed into the nearest one, nodding wordlessly to the students already in it, and soon they were off towards the castle.

There was little time to reminisce as they disembarked and were all whisked away to the Great Hall. Harry still felt a thrill as he walked in and saw the enchanted ceiling glitter with stars, its magic candles blazing as if they had never gone out. The tables were already filling up, and Harry realized he was expected to sit at the head table, with the other professors, so he edged his way around the room until he made it to the dais. "Potter," called a voice near his knee, and Harry looked down to see Professor Flitwick peering up at him through enormously thick glasses. "Professor Flitwick," Harry exclaimed, shaking his hand. "Good to see you, sir."

"And you," Flitwick said, climbing into his seat.

Harry found an empty chair near the far end of the table and had just sat down when he felt a rush of air and a large, breathless woman plunked into the seat beside him. "Mein Gott, I thought I vould be late!" she huffed, brushing back her windswept hair. She caught sight of Harry and turned towards him. "You must be zee new Flying Instructor, Herr…?"

"Potter," Harry offered, holding out his hand.

"I am Professor Brunhilde Schneider," she said, crushing his hand with her own. "Potions master. I hope you vill be very velcome here."

"Thanks," Harry gasped, surreptitiously massaging his fingers.

He scanned the milling students for his children and spotted James first, already seated at the Gryffindor table with his friends. Lily was farther down, head bent and barely acknowledging the girls around her. Harry and Ginny worried about her struggle to make friends. Maybe this year would be different for her.

Albus was similarly alone at the Slytherin table. Harry still had to remind himself that being a Slytherin wasn't an inherently bad thing, though he would never be used to one of his own children wearing that silver and green.

"Not Slytherin," he had begged the Sorting Hat all those years ago. Even as a child, he had refused to accept it. After Voldemort's death, he thought any trace of Slytherin had been purged from his being, along with Parseltongue and all the other ties to Voldemort.

Harry sighed to himself. Ginny always reproached him for overthinking about this. "It's nothing to do with you where Albus was sorted," she'd pointedly say. "Albus is his own person."

Harry glanced back at the Slytherin table. I wish he had a few mates, he thought. Maybe that would-

The chiming of metal on crystal echoed through the Great Hall and Harry saw McGonagall, suddenly present at the headmistress' seat, tapping a knife to her goblet. "Mr. Filch, if you would," she called.

Filch is still here?! Harry thought, amazed, and he craned his neck to see the old codger, but to his surprise he instead saw a sprightly young man jogging to the main doors. "Come along," he called, waving the first years in. Hagrid led the way, the seated students dodging the swing of his lantern as he passed, then he ambled up the stairs and took the empty seat beside Harry. "Hagrid, who's that?" Harry asked, nodding at the young man.

"That's young Davy Filch," Hagrid replied, stowing his lantern under the table. "Took over last year after Argus broke his hip. He's a cheery little chap. You'd never know he was Filch's nephew."

Harry was prevented from replying by Professor Tamby entering from the back room, carrying the Sorting Hat in both hands. "Attention," he called, his reedy voice half-buried under the first year's chatter.

"Quiet," McGonagall commanded, and silence instantly fell.

"Thank you, Headmistress," Tamby said. "Now, when I call your name, come sit here," he gestured to the stool behind him, "and I'll place the Sorting Hat on your head."

He took a parchment from his sleeve and unfurled it with some difficulty. "Amanda Argall."

A redheaded girl timidly ascended the dais, beginning the procession of first years up and down the steps as the Sorting Hat placed them in their houses. Harry's stomach rumbled as Tamby reached the R's and he glanced at the clock. I don't remember it taking forty bloody minutes in my day, he grumbled to himself.

Finally, after Daniel Zane was sorted into Hufflepuff and Tamby whisked the Sorting Hat away, McGonagall rose and called for attention. "I have a few announcements," she began. "First, I would like to remind all students that house common rooms are strictly limited to house members. Anyone caught in a common room that is not their own shall enjoy a month of detentions mulching the school gardens. Second, many of you know by now that Madame Chase has had to take an extended leave of absence. In the meantime, Mr. Harry Potter-"

A few students cheered and McGonagall gave them a severe look until they piped down. "As I was saying, Mr. Potter has kindly agreed to fill in as Flying Instructor in the interim. I will only say this once," she said, leaning slightly forward. "Mr. Potter is a highly respected figure in the Ministry of Magic. You may view him as some kind of celebrity, but we will not tolerate any harassment towards him. He is to be regarded as a Hogwarts teacher, and his privacy respected as such."

She leaned back, satisfied. "Let the feast begin."

The food instantly appeared on all tables, suddenly filling the air with every kind of pleasant aroma. Finally, Harry thought, immediately heaping potatoes onto his plate.

The next morning Harry was up with the sun, anxious to start the day. His chambers were in a tower just off the practice pitch, and in the distance he could see the morning sun striking the Quidditch goals. He dressed quickly and tucked Madame Chase's class schedule under his arm before jogging off to breakfast.

It was quite a walk to the Great Hall, farther than Harry remembered, and by the time he made it breakfast was already well underway. He piled eggs and sausages on his plate with one hand and unfurled the schedule with the other. Madame Chase had already planned out the rest of the term, thank heavens, with classes, practices and games already neatly ordered in little charts. She alternated class days with practice days, and the first Quidditch game wasn't until November eleventh.

"Good morning, Mr. Potter."

Harry looked up abruptly. "Good morning, Professor McGonagall."

She held out a rolled up parchment. "What's this?" Harry asked, taking it.

"Your new class roster," she replied. "It seems you had a few last-minute sign-ups."

Harry glanced over the parchment and couldn't help rolling his eyes. "Professor, I-" he began to say, but McGonagall was already in her chair eating marmalade toast. Harry turned back to the roster. Seventeen new sign ups to an already full class, he groaned to himself. He fished a quill from his pocket and spent the rest of breakfast working out the schedule. It took some doing, but by the time breakfast ended he had all seventeen students dispersed amongst the three classes. He downed the last of his pumpkin juice and left the Great Hall in the first wave of students heading to classes.

By the time he arrived at the practice field, he found nearly forty students milling about in the grass. Some of them held brooms of their own, while others were clustered around the bin of practice brooms and arguing over who would have which one. "Erm, hello," Harry called, "could I have everyone's attention, please?"

The class turned, delighted to see him, which made Harry uncomfortable. "Right, erm, Professor McGonagall turned in our new sign-ups to me just this morning, and it would seem the class is a bit overbooked."

Groans of disappointment swelled from the group and Harry waved his hands for quiet. "Hang on," he called quickly, "I was going to say I've had to redivide the classes, but everyone still has a place." He fished the schedule from his robes, then with dismay he realized he only had the one copy. "Multiplico," he muttered, tapping the list with his wand, and it immediately popped out a second copy. "Here's the schedule," he said, holding out the list. "If you aren't in this morning's group and are late to your correct class, I'll vouch for you."

The students lined up and took schedules almost faster than Harry could multiply them into existence. Many of them were pleased to discover they were indeed in the right class and happily returned to their brooms, while several others, who had not made it, groaned in frustration and took off sprinting towards the nearest castle entrances. "Sorry for the confusion," Harry apologized, jamming his wand back into his pocket, "but I'll try to be more organized in the future. Everyone grab a broom and form two lines, facing me."

As the students formed ranks he studied them closely, wondering if any of them were secretly part of the Wanderers. Anyone with sense would avoid him and stay under the radar, but experience had taught him that the most conniving plotters always hid in plain sight, even in positions of power or favor. It was just as likely, therefore, that some of the Wanderers faced him now, waiting expectantly beside their brooms. If Harry had been back at the Ministry, he would have questioned each one until someone talked, but Auror methods would not work here. "Everyone stand on the left side of your broom," he called instead, taking a wide stance between the two rows of students. "Hold your hand over the broom, and say, "Up!" as firmly as you can."

The students eagerly obeyed, with mixed success. Most of their brooms lazily wafted upwards, like sulky teenagers answering their mother's call, while a few lay stubbornly on the ground, ignoring their summons completely. "Come on, show it who's boss!" Harry called. One broom immediately flew straight up, catching his eye, and he turned to see a pleased older boy gripping a practice broom. "Well spotted," he called, walking towards the boy, "it seems you know what you're doing."

The boy, a lean, pale figure with blonde hair and a cool smirk, broadened his expression into a grin. "Thank you, sir," he said.

"You must be at least a fifth year," Harry commented, giving him a once-over, "You know this is a beginner's class, don't you?"

"Sixth year," the boy amended, "and yes sir, I do. My mother was always afraid of me getting hurt on a broom and forbade me from taking any flying classes, but Dad convinced her this year, since I'm nearly of age now. He said I'm old enough to start taking some risks."

Everyone was holding their brooms now and Harry gave him a nod. "Well, let's see what you can do, Mr. …?"

"Reed, sir," the boy offered, "Tiberius Reed."

The name rang familiar, but Harry didn't press the topic now. "Well done, everyone," he called, turning back to the group. "Now mount up, and we'll try a gentle liftoff."

Lily entered Charms class and was going to take a seat near the back when she noticed Melba Philpotts and her minions eyeing her. "Like what you see?" she challenged.

"We're not sure what we see, actually," Melba replied. "You don't look like anyone, you know. One would think that with a Quidditch correspondent and the Boy Who Lived as her parents, you'd be a bit more remarkable."

"Maybe if she brushed her hair once in a while," one of the other girls sniggered.

Lily resisted the urge to smooth down her ponytail.

"How is she to tame all that horsehair?" Melba wondered. "At least it matches her face." She gave Lily a gut-wrenching sneer. "Maybe we should call you Filly from now on."

Professor Flitwick entered the room and Lily strode past Melba without a word, settling into a seat a few rows back from her and her gang. She surreptitiously tucked a few loose strands of hair behind her ear and tried to listen to what the professor was saying, but all she could do instead was stare at the back of Melba's head. At one point, while Flitwick was demonstrating the various wand flourishes used to boil a kettle, Melba glanced behind and smirked when she caught Lily glaring at her. She mouthed the word Filly and pretended to neigh silently. Lily was about to do her best to boil Melba's brain, her wand already pointed directly at her head, when suddenly her chair was yanked out from under her and she tumbled to the floor in a heap. The other students laughed and Lily felt tears well up.

"Quite enough, quite enough!" Flitwick called, tapping his wand on the desk. "We'll not be having those shenanigans in my class, especially on the first day!"

The school bell clanged and the students scurried to the door, jostling each other with book backs and rolls of parchment. "We'll be testing that on Friday, so make sure you practice!" Flitwick shouted.

Lily got back onto her feet, swiped away a rogue tear and started shoving things into her bag.

"Sorry about that."

She looked up into the face of a tall, blonde-haired girl, whose green eyes were boring into her intensely. "Sorry for what?" Lily mumbled.

"The chair. I didn't mean for you to fall like that."

"You yanked my chair?!" Lily said indignantly.

"I saw you drawing wand on that doughnut girl," the girl rebutted, "I had to do something."

Lily was confused. "Doughnut girl?" she repeated.

The tall girl shrugged. "I don't know her name, but I saw her stuffing her face with powdered doughnuts at breakfast. It was like watching a pig eat its own baby."

Lily giggled and her tears began to subside. "Your accent-"

"American, guilty," the girl interrupted with a grin. "I'm Savannah Logan, but I go by Vanna."

"What are you doing at Hogwarts?" Lily blurted.

The bell clanged again and Vanna's eyes flicked upwards. "Walk and talk," she said, slinging her bag over one shoulder. Lily hurried to follow her out into the corridor, where they merged into the river of students jogging to their next class. Vanna was easy to follow, however, as she stood head and shoulders above most of the students, except maybe the sixth and seventh year boys. She glanced back a couple of times to make sure Lily hadn't gotten lost, and Lily endeavored to keep up. "Come on, short stuff," she called, making a sudden left through an archway and down several flights of stairs. The crowd thinned dramatically and Lily was finally able to catch up to her. "Blimey, you walk fast," she panted.

"Can't help it," Vanna said lightly, "I'm half-giant."

Lily's jaw dropped. "Really? Like Hagrid?"

"No, not really," Vanna laughed, "I'm just yanking your chain. My ancestors were Vikings, or so my dad says. My family emigrated from Norway to Michigan in the thirties, and that's where we stayed."

"You haven't answered my question," Lily said pointedly.

"I went to Ilvermorny until this year, but my parents applied for me to have a year abroad," Vanna explained, expertly dodging a squadron of frantic first years. "Principal Rowland took some convincing, but here I am, Hogwarts' first American exchange student."

Lily hadn't thought such a thing was possible. "Aren't you terribly lonely?" she asked.

Vanna paused and turned to her. "No," she said emphatically, "and I'll tell you why. Most kids think they want an adventure, but when an adventure comes knocking, they get scared and back down. They wanna stay a kid, because kids are protected. I don't need protecting. I'm ready to have as many adventures as possible, and I wasn't gonna find them in Ilvermorny." She grinned again. "You should go into class, I hear Professor Schneider likes to embarrass latecomers."

Lily was pleasantly surprised to find herself standing outside of Potions. "How did you know…?" she turned back and found herself standing alone in the corridor. She faced the door and heaved a sigh. "I want to have an adventure," she whispered, and with new confidence she thrust open the door.