March, 2031
United States of America

Mary Sue Potter pulled the false bottom out of the cupboard, and was startled by a large chocolate rabbit. Her cousin had obviously discovered this hiding place. Discovered it, claimed it, and decided to use it to hide sugar-free Easter candy. Mary hesitated, pushed the rabbit aside, and saw her notebook lying in the back. The spell sealing the notebook shut was intact, and Mary was contemplating the cleverness of charming the rest of her top-secret materials to be invisible and storing them in the ruined hiding place. Surely, anyone snooping around would think the candy was the only thing hidden here. But it was too late; a car had just pulled up the driveway.

Dudley Dursley was home.

Mary stuffed her notebooks back into her bag. She'd have to stick them in the back of her underwear drawer instead, which felt much less important but was probably safer. Dudley was humming as he hung his coat in the hallway.

"Nice date, then?" Mary asked. Her cousin was home early, but it seemed to have gone well this time.

Dudley smiled distantly. "We're seeing each other tomorrow. The aquarium's doing a special exhibit on dolphins," he said.

All things considered, the years had been kind to Dudley. He hadn't gained back the weight he'd lost as a teenager, though he wasn't what anyone would call thin. At fifty-one, Dudley was solid, with a decent paunch, an occasionally ruddy face, and a full head of thick blond hair with only a few gray streaks. He managed a drill recycling plant and was usually more keen to watch television than do anything else on weekends, though recent romantic developments were beginning to take precedence. In the past thirty years he'd lost both parents, his aunt Marge, and his cousin Harry.

Mary had lived with Dudley for as long as she could remember, and was viewing their impending separation with anticipation and dread. She'd always been happy in Dudley's house, though they'd moved around a lot when she was little. These days they shared a three-bedroom townhouse near Boston, close to the university where Mary had earned a PhD in Theoretic Temporal Magic.

"And when do I get to meet this amazing woman?"

"Soon," Dudley sighed, settling in front of the television in the den. His eyes were dreamily fixed on an infomercial for a magical vegetable peeler.

"It had better be soon, I'm leaving in a week," Mary said.

Dudley frowned. "But you'll be back in April, won't you?"

"That's the plan," Mary muttered, thinking that if all went according to plan, she wouldn't be back at all.

"Plenty of time, then." Dudley's eyes were glazed as he watched a spokesperson shred a dozen potato skins at once. He probably didn't even realize what he was watching; after all these years, Dudley was still a bit spooked by overt displays of magic.

"Goodnight, Dudley."

"'Night," Dudley said.

Mary left her cousin to his post-date ruminations. She carried her full yet feather-light bag up the stairs, oddly disappointed that her cousin hadn't at least asked what she was doing at home on a Friday night.

Perhaps Dudley had given up on her, Mary reflected. It was a bit odd for a woman of twenty-seven to live with her family when she had the money and the means to move out after college, but Mary had never got around to finding her own place. Enough people in her life had left her, and she wasn't going to leave her only remaining family for an empty apartment. Mary's father, the famous Harry Potter, had died even before she was born. Mary's mother, Ginny Weasley (her parents hadn't gotten around to marriage) had followed Dudley to the States when she realized she was pregnant, and stayed long enough that Mary could just remember her mother's face. Ginny had left when Mary was very young, to fight and die in the war against Voldemort, like so many others.

The muggles found out, of course. A few important government officials had always known, but Voldemort's rise to power in Britain became impossible to hide after the Battle of Hogwarts. Civilians, both magic and muggle, were evacuated first to the continent, and then to the Americas, Australia, Africa, and Asia. Voldemort's power had grown beyond imagining, and he gave up all pretense of sparing the magically pure. Hundreds of thousands died, and by 2010 the muggles had had enough.

First, muggles tried for an assassination. They knew about horcruxes, but didn't quite believe such things existed. When none of their agents survived their attempts, the muggles turned to science. They had somehow got samples of Voldemort's DNA, and designed a virus to target and kill Voldemort alone. Unfortunately, like a bad sci-fi movie, the virus mutated. The resulting plague swept through Europe and North Africa, killing hundreds of millions, both magic and non-magic people, yet leaving Voldemort himself untouched.

Finally, the muggles gave up on subtlety and sent a nuclear warhead directly to Voldemort's stronghold. Voldemort was declared dead on May first, 2011. No body was ever found, but no living thing could be found within a hundred miles of the crater that marked Voldemort's last known location. Despite a vaccine eliminating all traces of the plague, Europe was now sparsely populated. The British Isles were still quarantined, twenty years after the war's end. Mary knew it wouldn't be easy to make it to London, but she couldn't save the world from Boston.

Like most great ideas, travelling through time to stop Voldemort's belonged to Hermione Granger. Hermione had made extensive notes on both of Voldemort's rises to power, on her own years at Hogwarts, and on the war after Hogwarts was lost. Information on known time travel spells filled two thick spiral notebooks. Hermione had made it her mission to know everything about the war and the events leading up to it, until she'd been killed while trying to sneak into the Ministry of Magic with Ron Weasley in 2001. Most of Hermione's research now resided in a corner in Mary's dresser, magically sealed and invisible beneath a pile of frilly under-things. Soon, Mary would leave all she'd ever known to fulfill Hermione's vision.

Mary sat uneasily on her bed, drawing her legs up to her chest. Hermione had seen time travel as a last resort, but she'd died before getting a chance to use it. Mary had found Hermione's notes years ago, and decided her fate at the age of thirteen. After years of hard work, Mary would be leaving Boston in just one week, and somehow packing wasn't something she needed to do until tomorrow.

Mary swore she was never flying coach again. Intellectually, Mary knew that flying in airplanes was a lot better than it used to be, especially with magic shields in place around the engines and the cabin so you didn't need to worry about dying in a crash. Airplanes were also much more comfortable than transcontinental portkeys, which had left Mary feeling sick for three days when she visited China on a school trip. But somehow the muggle-magic cooperation of the past twenty-five years hadn't included undetectable extension charms on airplanes.

Mary was squashed between two large tourists, and the teenage boy seated behind her had been kicking her chair since before they'd taken off from New York. Fortunately for the boy, Mary had been forced to pack her wand in her checked luggage. It was also lucky that the flight to Paris only took three hours. With effort, Mary concentrated on her laptop and fought the urge to practice her wandless hexes. The last thing she needed was to get into trouble with the French Magic-Non-Magic Cooperation Office.

Legend said that Merlin began life as an old man, and grew younger as time passed. Modern magical theorists held that Merlin's brand of time travel had such deadly side-effects that no one besides Merlin had ever managed it. Of course, time travel spells were also extremely illegal, and the penalties for those found attempting it were worse than the side-effects. Mary had told no one what she was up to, ensuring complete secrecy and that no one else need be in trouble were she caught.

Partial records of Merlin's spell existed, but the most complete of these had resided in the now-destroyed library of Hogwarts. The surviving equations baffled arithmancy experts, who insisted no one could calculate them fast enough for the time travel spell to work. The lists of ingredients for the spell's potion were all written in metaphors from a language no one had spoken in over a thousand years. The spell's many side-effects daunted most would-be time travelers; what good was travelling back in time when your memory didn't travel with you, and the price in years left you too old and feeble to do anything? But Mary knew she could do it. She'd been planning to go back in time for more than half her life.

The arithmancy equations were the easy part. Those experts who'd said the calculations weren't possible hadn't counted on computers. The field of Magic Computer Science was growing rapidly, and Mary was skilled enough to write a program that would take into account the particulars and vagaries of her arithmancy. Complex ancient metaphors for potions ingredients were a snap, when one had access to an internet forum filled with bickering linguists specializing in ancient Germanic languages. Memory loss went hand in hand with the years of life lost to the spell; all Mary had to do was cast a quick electro-stabilization charm before she downed the potion, and the contents of her brain would transfer without loss to her new, aged body.

Mary wasn't looking forward to being an old woman at the age of twenty-seven. She hadn't properly enjoyed her youth, having spent so many years deciphering ancient time travel spells and comparing them to tried and true modern methods. Mary knew she was uncommonly beautiful, with clear skin, brilliant green eyes, dark red hair, long legs, and fantastic breasts. Mary was also very clever, having graduated from the Salem Academy of Sorcery two years early, and earning a double undergraduate degree before attempting graduate school. Unfortunately, Mary had a large ego which negated many of her attractive qualities and made finding friends difficult.

Mary was just contemplating her own brilliance in writing an arithmancy subroutine for magicalculus when her laptop chirped and a little cartoon owl began dancing at the bottom of her screen. Mary clicked it, and found that Dudley had sent her a virtual postcard with a picture of a snail. She grinned, and began typing a reply.

An hour later, Mary was struggling through the crowd headed for the customs counter. Soon, Mary was free of the crowd and had collected her large, chartreuse suitcase. She was glad to slip her wand back inside her jacket sleeve, having felt bereft without it. Mary was just starting to look around for her contact, striding toward a large sign as though she knew where she was going, when a man with bright turquoise hair shouted and waved at her.

"Mary, Ma-rie! Over here!"

People were starting to stare. Mary flushed and changed direction.

"Mary!"

Without warning, he hugged her. Mary resisted the urge to hex him. Teddy Lupin was an old family friend, though they'd never met in person, and wasn't to know that Mary was unusually grumpy from her flight.

"Hello, Teddy," Mary said, withdrawing her suitcase from Teddy's ribs. "You're much louder in person than over the internet."

Teddy smiled broadly. "I'm much more of everything in person, if you know what I mean and I think you do."

Mary blinked. She didn't know what he meant, and was inclined to think that one of them was very confused. "So, I'm hoping that you know a way out of here that doesn't involve battling morning rush-hour into the city."

"Oui, madame," Teddy said, offering Mary his arm and flicking his wand at her suitcase. He steered her to an apparition point roped off from the general bustle of the airport. The suitcase floated along beside them. "Right then," he said, reaching for the suitcase. "My place?"

Next second, Teddy turned on his heel and pulled Mary after him. They disappeared with a crack and reappeared in a well-lit hallway. Teddy opened the door numbered 4B, and motioned for Mary to precede him inside.

"It's ... lovely," said Mary, lying. The apartment had large windows, bathing the sitting room in morning light. Elegant couches were arranged around a low table before the fireplace. The wooden furnishings looked antique, and Mary just caught the gleam of stainless-steel appliances in the kitchen off to the left. It really would have been lovely, if every elevated surface and a good portion of the floor weren't covered in untidy stacks of papers.

"My gran says the same thing," said Teddy. "Though she generally says it after she's 'cleaned things up a bit' by stacking up all my papers and ruining my perfectly organized files."

Mary laughed, feeling better than she had since before stepping on the plane.

"Now, for your accommodations."

Teddy showed Mary to a small bedroom off a hallway to the left. It had an ensuite bathroom and a window with a view of the building across the alley. Mary dropped her suitcase at the foot of the bed, and went to freshen up while Teddy made them both coffee.

"I feel almost like a person again," said Mary, draining half her cup in one swallow. "I think I hate airplanes more than portkeys."

"Shall we get down to business, or pleasure?" Asked Teddy, waggling his eyebrows.

"Pleasure?"

"You're in Paris, Mary. Art museums, great food, and I've got the day off work. I thought I could take you around the city, if you'd like."

Mary thought about it. She'd never been to Paris, and playing sightseer for a day sounded a lot better than pouring over her calculations again. "All right," Mary said. "Let's go to the Eiffel Tower first."

Teddy protested that the Eiffel Tower was just a tourist trap, but disapparated with Mary to the Champ de Mars anyway.

Mary did have wonderful time with Teddy, apparating to at least a dozen points in Paris. While the whole population of Europe had been decimated during the war, Paris seemed to have recovered completely. The city was alive with Parisians, pigeons, and tourists. Everywhere they went, there were at least a hundred other people milling around. They had just finished dinner, and Mary was feeling rather more cheerful than normal, thanks to the wine.

They walked slowly back to Teddy's apartment, enjoying the cool Spring air.

"To business?" Mary asked, after a lull in the conversation.

"Hmm," said Teddy.

"I know I've got to get up early tomorrow," Mary continued. "But I don't know what time the portkey's set for."

"8 o'clock," said Teddy. "And the return is for twelve hours later. You don't have to get up that early."

They dodged an oncoming group of teenagers, all wearing navy blue jackets and talking loudly in French.

"Seeing as my watch says that 8 AM here is the same as 2 AM at home, eight in the morning is sounding very early."

"Ah, but it's only ten. The really good clubs haven't even opened yet."

"No more," Mary groaned. "All I want to do now is sleep and not feel nervous about tomorrow."

Turning at last onto Teddy's street, Mary saw the outside of his apartment building for the first time. She was struck again by how old everything here seemed to be, and how elegant the buildings looked. Most of the places she'd been to in America weren't more than two hundred years old, and tended to have been built in the 1970s. They paused at the entrance.

"How old is this building?" Mary asked.

"About eighty years or so," Teddy replied. "It was built after the second world war."

"I thought it was older," said Mary, peering up at it. She could almost feel Teddy's eyes on her face, and hoped she didn't look flushed.

"Still nervous?"

"I'll stop being nervous when it's done," said Mary.

"This time tomorrow, then?"

"By this time tomorrow I'll be in Greece," Mary lied. It wasn't that she didn't trust Teddy. If the unthinkable happened, if she were caught, only Mary would be held responsible.

"I can think of one thing that might distract you," said Teddy, winking. "No pressure, though." He turned, and went inside, leaving the door open behind him.

Mary looked down at her hands, thinking. She'd known Teddy for years, even if they'd met in person for the first time today. Very soon, Mary was going to be an old woman. And everybody knew what they said about Metamorphmagi. Decision made, Mary followed Teddy into the apartment.

Next morning, Mary awoke before the sun rose. She stumbled groggily into her bathroom, and revived herself by showering. By the time she emerged, fully dressed and packed, Teddy had already made them both coffee and breakfast.

When they had both eaten, and Mary was nursing her second cup of coffee, Teddy brought out the portkey.

"This is it," said Teddy. "Leaves in twenty minutes, assuming you still want to go."

"Of course I'm still going," said Mary. She eyed the portkey, feeling a familiar mixture of eagerness and trepidation. The portkey was a shiny metal disk with an "Official European Portkey" stamp on one side, along with a serial number and an "Unauthorized Use Strictly Forbidden" warning. Mary was relieved that it wasn't a smelly old piece of garbage, as most portkeys had been before magical society had reintegrated.

"It's just that it's very dangerous," Teddy said. "No one's set foot on Great Britain in twenty years and lived to tell about it. People have gone, but they don't come back."

"No one's likely to say they've been and come back if they get thrown in jail for admitting it," said Mary. "And anyway, I'm only going to be flying a broom over Scotland. You've done that yourself, haven't you?"

Teddy became very interested in the remains of his croissant. He muttered something that sounded very much like "twice."

"Then I don't see what the big deal is," said Mary. "I'll take the portkey to the Isle of Drear, take a broom around Scotland, not landing for any reason, and then the portkey will take me back to the Portkey Office in Normandy, and I'll catch another portkey to Greece. This time tomorrow, I'll be at the beach."

"If you get caught-"

"I won't get caught."

"Look, any big spells you cast while you're there will be noticed. It's fine on the Isle of Drear, because they don't monitor it closely. But on the mainland, the Ministry have got detecting spells set up so that any powerful magic that goes on gets investigated. You can't cast a patronus, and they say there are still dementors lurking around. You can't even apparate anywhere without setting off alarms," said Teddy.

"I know all that," said Mary. "I promise to be careful. But I decided to do this a long time ago, and I'm sticking to my plan."

For a moment, Teddy didn't speak. Then, "Fine, but if I don't hear from you after you get to Greece-"

"I'll send you an email," said Mary. "International portkeys make me sick. And what's with this sudden show of concern?" Mary's eyes narrowed. "This isn't some 'we slept together and now I must boss you around' guy thing, is it?"

"Can't a guy be worried about his old friend risking prison for a few hours of illegal sightseeing?" asked Teddy, trying to look charmingly wounded.

Mary rolled her eyes. "Be as worried as you like, but I'm going to be fine. But not if I miss the portkey," Mary said, as the portkey began to glow, signifying that there were only sixty seconds before it left.

Mary stood, pulling on her coat and then collecting her suitcase from the hall. Teddy stayed put, but Mary thought she saw his wand hand twitch. Mary picked up the portkey, and waited, feeling awkward. Should there have been a hug? Mary didn't know, and it would look even stranger if she tried after she'd already got the portkey.

"Thanks for letting me stay," said Mary. "And for the portkey," she added.

"No problem," said Teddy. "I'll see you in Greece, all right?"

Before Mary could respond, the portkey tugged at her navel, and she was gone.

Mary managed to land on her feet on the Isle of Drear, but immediately dropped to her knees and vomited her breakfast. Getting to her feet, Mary waved her wand to vanish the mess and rinsed out her mouth with a bottle of water from her pocket. She hated portkeys.

The place certainly lived up to its name, Mary thought. The Isle of Drear was covered in gray fog. The sun had risen over an hour ago, but it still felt cold. Mary looked into the dim sky, and was unsurprised to feel a light rain on her face. Luckily, the five-limbed man-eating quintapeds who lived on the island were nowhere to be seen. The Isle of Drear had long been made unplottable, to stop people from visiting and being eaten by the quintapeds, and no one ever visited, apart from zoologists who'd jumped through a dozen hoops to get clearance. Teddy only had a portkey to it because he had a few well placed friends in the EU's portkey offices.

"Lousy weather for flying," Mary said to herself. Turning to her suitcase, Mary cast a few detection charms of her own. Sure enough, there was a tracer spell on both herself and the suitcase. Mary tutted, and transferred both charms to the suitcase. It was rather perceptive of Teddy to suspect that she wasn't being entirely honest with him about her plans, but he wasn't in Mary's league when it came to spellwork. Mary pulled out her laptop and typed a quick "I survived! Meet for drinks on Saturday?" email to Teddy, and set her email provider to send it in thirteen hours. Mary planned to have gone back in time by Thursday, the day after tomorrow, and wasn't worried that Teddy would miss her.

Mary closed the laptop, and tucked it back into one of the magically expanded pockets of her coat. She knelt again, and opened her suitcase. It wasn't as neat as she would have liked, and Mary had to dig through a pile of swimsuits before she found her prize: a seemingly small black shoulder bag, also equipped with an undetectable extension charm. This bag held Mary's cauldron, the potion she'd been dutifully brewing for thirteen months, a small, already disillusioned and shielded tent, the notebooks holding Hermione's research, an illegal portkey, and a broomstick.

Mary loved to fly, but she found broomsticks cumbersome. The broomstick, a sturdy Cleansweep Seventeen, would be staying on the island. Mary extracted the broom and the illegal portkey and laid them next to her suitcase. The black bag went into another of her pockets.

With a tap of her wand, the illegal portkey glowed gold for a moment, then resumed looking like an ordinary pair of socks. Mary tossed it in with the rest of the clothes. Closing the suitcase, Mary laid the EU portkey on top of it, and cast a somebody-else's-problem charm around it to keep the quintapeds away. In twelve hours, the suitcase would vanish, appear in Normandy for five minutes, and then disappear to a locker in Athens. She was ready.

Mary stood, took a last look at the broomstick and the chartreuse suitcase, and concentrated hard. With a faint pop, Mary transformed into a peregrine falcon.

Naturally, Mary was an unregistered animagus. It had been a difficult spell to perfect by herself, but Mary had managed her first successful transformation when she was just fourteen. It had been another three years before Mary had managed to consistently transform with her clothes as well, so that she didn't have to worry about being caught naked and wandless. Mary was proud to say that she'd only gotten herself hospitalized once when attempting the dangerous transformation, and the doctor hadn't suspected a thing after reversing Mary's bungled spell. Mary considered herself to be quite lucky to have such a useful animagus form, and flew as often as she could at home. She'd never flown as far as she needed to now, but Mary had a few strengthening solutions tucked away, just in case.

With a final look around the Isle of Drear, Mary raised her wings, and flew high into the air. London was many miles to the south, and Mary was on a schedule.

Mary had been flying for nearly five hours and her arms were getting tired. Just when she had resolved to find a nice wooded area to rest for lunch, she saw it: high cliffs, a forest of dead trees, masonry tumbled along a brown hill, and a vast sandy crater that had once been a lake. This was where Hogwarts had stood. Mary circled the largest of the cliffs once, and landed lightly on human feet. All was quiet.

You'd never know this was where the greatest wizarding school in Europe had been founded, Mary reflected. All that could be seen of the castle were bits of crumbled walls dotting the hill. A single, broken column sat precariously at the edge of the cliff, as though a sudden wind was all that would be needed to send it to the sand below. Even the foundations were gone.

Mary turned to look at the once Forbidden Forest. Nothing moved within. The Battle of Hogwarts had left very few survivors, and Mary wondered morbidly where all the bodies were. The Resistance had lost the battle, and Voldemort's forces hadn't been known for cleaning up after themselves. The whole area gave Mary the creeps, and she resolved to find a place to rest in the ruins of Hogsmeade. Just as Mary began picking her way down to the sandy lake, a pearly white figure rose out of the ground before her. Mary stumbled once, but didn't fall.

"Hello," said the figure. It was the ghost of a young woman, colorless and translucent, wearing old-fashioned robes and radish earrings.

"Hi," said Mary, dearly hoping that the ghost wasn't part of a security system designed to keep out trespassers.

"It's been a long time since anybody visited," said the ghost. "Are you going to stay?"

"Um, no," said Mary. "I'm just passing through. I'll leave now, if you like."

"I'd like it if you'd stay. I don't get to talk to many people, you know," the ghost said. "I'm the ghost of Luna Lovegood, by the way."

"Really?" Mary asked, gaping a little. "I've read all about you! Though, I wouldn't have thought Luna Lovegood would choose to become a ghost."

"Well, Luna died very young, and wanted to know what it was like to be a ghost, able to walk through things and all. So she left a little imprint, and then went off to the afterlife," said the ghost of Luna.

"It's just-I didn't expect to meet anyone here, and you're Luna Lovegood, and it would be silly to ask for an autograph, wouldn't it?"

"I'm not Luna Lovegood; I'm the ghost of Luna Lovegood," the ghost corrected. "And I can't hold a pen."

"Oh," said Mary, feeling foolish. "Are there other ghosts here?"

"They all left. I think they've all gone down to the continent, but I like it here," said the ghost. "It's really lovely, and there are many creatures still in the forest. But I do get lonely, with no one else to talk to."

"Um, you're not here to prevent tourists and people from poking around Hogwarts, are you?" Mary asked, trying to look causal.

"No, but I do watch for visitors. Would you like to take a look around? The great hall was just over there; that's where I died," the ghost of Luna said.

"Sure."

The ghost of Luna grinned at Mary, and glided along a rocky slope to a large, paved flat space, about the size of a football field. Mary hurried after her.

"The walls are all gone, but you can still see the ceiling," the ghost said, rising a few feet in the air and then reclining, as though on an invisible bed. Her head was level with Mary's. "You haven't told me you name, but perhaps you are being secretive. My last visitor was secretive, too."

"Sorry, I didn't mean to keep it a secret. I'm called Mary Sue, or just Mary, really. 'Mary Sue' is only just for when there's another Mary in the room." Mary craned her neck to look up, but all she could see was sky.

"There aren't any other Marys here," said the ghost, now gazing at Mary with large, shimmering eyes.

Mary swallowed, and kept her eyes fixed on the gray clouds above. "I know the ceiling of the great hall was enchanted to look like the sky, but I'm only seeing the ordinary sky."

"You can't see it properly that way. It helps to lie back," the ghost said. The ghost of Luna floated close to Mary, and translucent hands suddenly gripped Mary's shoulders.

Mary gasped; the hands passed right through her, but were icy cold, and Mary flinched and fell back. But she didn't land on the stone floor. The ground had opened beneath her, and Mary fell twenty feet and landed on her back in a pile of slithering flesh.

"What," Mary started to say, but a lurid green snake, as thick as her leg, had already wound its way around her neck. The pit of snakes writhed beneath her, entangling her arms and legs. Mary flexed her wrist, trying to get her wand in to her hand. A slender serpent saw what she was doing, coiled around Mary's wand, and squeezed. The wand snapped.

Mary tried not to panic. Panicking never worked. The ghost of Luna drifted down, lying beside Mary. The snakes shrank from the ghost, rolling over Mary's legs instead.

"Luna," Mary wheezed, barely able to breathe. "Help-"

"I told you, I'm not Luna Lovegood. I'm the ghost of Luna Lovegood."