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Outsmarting the Fidelius

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“Practical” was how Lily Evans’ family described her. Ruthless and pragmatic , the Sorting Hat said, and daring, oh, and a nice thirst to prove yourself… now where to put you? 

She wasn’t surprised when it called out “GRYFFINDOR”. She was a little sad when, five minutes later, her best friend went to “SLYTHERIN.” 

But Lily Evans was a practical girl and didn’t see why anything like House loyalties should stop her. 


“I don’t need help from a mudblood ,” Severus yelled, and sixteen-year-old Lily felt herself freeze and harden. 

The Sorting Hat had not been enough to stop her. Nor had the pureblood bigots or the slurs or the stares or the whispers or James Potter. But this—hearing the word that had been spat at her in hate turned on her by her best friend—this she could not countenance. 

“Fine then,” she said coldly, already turning away. 

He came to her, later, apologizing, begging forgiveness. Later Lily would look back and regret her own merciless rejection. Severus had been under fire in a literal way among his own House mates and with the benefit of adult perspective she knew he would have been punished had he accepted her public defense. But at sixteen in a war of ideals it had all seemed so clear. 

Of course, by the time she felt regret, it was already too late. 


“Go out with me,” James Potter said for the Merlin-only-knew-nth time, and Lily snapped. 

“No more pranks,” she hissed. “No more bullying. If you want me to go on a date with you, Potter, you’ll bloody well have to earn it. The next Hogsmeade weekend’s in a month and a half. I’ll be surprised if you can last that long. And if you can’t, then you’ll never bother me again, clear?”

And she would be surprised, though there was a determined glint in Potter’s eye. Lily knew full well you shouldn’t go giving Gryffindors ultimatums willy-nilly. (Or, for that matter, Slytherins.) But if he lost, he would have to leave her alone—it had been a public bet—and if he won, well, she’d gotten him to lay off all the kids the ‘Marauders’ bothered. 


One date turned into two, which turned into shared meals in the Great Hall and shared library tables and the realization that James Potter was adequately clever for all he didn’t care about marks. And why should he? Pureblood, handsome, wealthy as sin, James Potter would never (Lily thought with some bitterness) need to worry about anything as silly as whether he’d get a job. He could walk into nearly any position he liked after graduation and find his way to the top paved silky smooth. 

Sirius Black was another matter. Lily did not like him, nor he her. Everything was so personal: an invite to do a Transfiguration essay was her stealing James from him. A comment about bullying Slytherins really meant that she was trying to ruin his fun. Remus’ company was passable, even if he was a pushover; and Peter, for all his anxiety, was a sweet boy Lily rather liked. But Sirius, well. 

“She’s ruining us,” Lily overheard him saying. “We’re the Marauders! We don’t ditch each other to run off with some bint!” 

“She’s not some bint,” James snapped, “she’s brilliant and beautiful and—and I think I love her, Sirius, okay? Not like when I was thirteen and just saying dumb shite, I mean, I really think I love her.”

There was a pause in which Lily slipped away from the room where they stored their prank supplies (and that they thought was secret). 

So. That was… informative. Lily smiled when he came back to the Gryffindor commons and offered him a caramel from the box at her elbow and thought about what it might mean to have handsome, wealthy, pureblood James Potter’s love. 


They married under the light of a full moon in the spring of 1979, almost a year to the day after graduation. James’ grandmother Dorea Potter had insisted on a traditional ceremony and Lily hadn’t protested. 

Her parents were dead. Her sister didn’t want to attend. There was nothing left for her in the Muggle world, no traditions, no customs, no home. So Lily donned red dress robes as was the wixen way and braided flowers into her hair and walked barefoot to meet her husband. They swore themselves to each other in body and heart, in blood and magic, and the Potter family legacy settled on her shoulders like a heavy winter cloak. 

“Lady Potter,” James said, his face radiant. 

“Lord Potter,” Lily murmured. Magic crackled from her scalp to her toes and it had nothing to do with the kiss that sealed their vows. 

God, no wonder purebloods were such arrogant prats, if they felt like this all the time. Lily could already tell she was no more powerful , but the richness of the magic, the intimacy with which it embraced her—she never wanted to give that up. 


They moved into a cottage in Godric’s Hollow, since Charlus and Dorea still lived in the ancestral manor and Fleamont and Euphemia in their London townhouse. A young elf named Marney was theirs, which was fortunate, since Lily had never been overfond of housework. She quickly struck up a friendship with the little thing and James often came downstairs to find his house-elf and his wife sharing tea while Lily taught Marney about magical theory.

In fact, it was Marney who first told Lily about the Potter library, and thus accidentally incited Lily and James’ first major fight. Lily was irate James had never told her such a thing existed. It had never even occurred to James that he might have to tell her. 

Culture shock , Lily thought angrily, hours later and elbow-deep in books. No child of hers would endure that. No child of hers would grow up ignorant and isolated or spat on and called mudblood in the halls. 


“Four weeks pregnant,” the healer said, and Lily slumped back into the uncomfortable hospital chair. 

When she had defiantly imagined tearing down the Death Eaters and reshaping the magical world into a better place for her child, she had not expected such a child to come so soon. 

“Contraception charms aren’t always perfect,” the healer said when Lily asked how this was possible. “Have you been taking the potion?” 

“What potion?” 

That became their second fight: that James never once mentioned there was a contraception potion for witches , because the standard charm guarding against social disease and accidental pregnancy wasn’t perfect.

This time the cultural differences felt less exasperating and more… dangerous. 

“We’re going to be raising a baby in a war zone ,” Lily hissed, “because you couldn’t be arsed to have an honest conversation with me about reproductive magic!” 

“How was I supposed to know you didn’t know it!” James yelled. 

“How was I supposed to know the charm wasn’t perfect!” she yelled back. 

Of course, she could have looked it up, and Lily later admitted she too was at fault. Could have looked it up, or gone to Madam Pomfrey, or done a half-dozen other things—but she hadn’t, and James hadn’t thought to ask, and now here they were. 

And it was still her child. Lily rested her hands on the faint swelling in her stomach at night and thought: I will love you, I will protect you, I will die for you if I must, but you will not endure what I had to. 


James still went on raids but Lily did not. Already there were rumors of the Dark Lord surviving unsurvivable curses, performing impossible magics. The Potters unanimously refused to risk their House’s last Heir in battle and so Lily threw herself into research. She drank in the Potter library one book at a time and raided the houses of any other Order member that she could. Shacklebolt, Meadowes, Ogden, they all had venerable caches of magical knowledge, and they all gladly contributed. 

Thus Lily passed the months of her pregnancy immersed in ancient enchantments and esoteric theory and strange, lost runic languages. She published articles and did potions research at the kitchen table. Ideas flashed in her brain like lightning and at night when they fucked she turned that same passion on her husband. 

Good, loyal, brave, mischievous James, who won duels with soapsuds charms and called her Lily-billy and transfigured her a ruby and onyx chess set as a Yule gift. Lily wasn’t sure if this was love but he made her feel safe and warm and happy and she knew he would love their child with all his heart. And that was more than enough. 

And when Harold James Potter slid from her body at eleven fifty-seven p.m. on the thirty-first of July, 1980, Lily thought of the time and date only in her astonishment that she had endured thirty hours of labor; and even that was lost in the wash of fierce, fire-bright love that came when she held her son for the first time. 

James cried. Lily did not. 


Their old Headmaster came to them speaking of a prophecy and a danger and a need for secrecy. Lily held her son to her chest and watched in silence while James raged and shouted. 

Her son, or her godson Neville, was to defeat Lord Voldemort. 

Somewhere deep inside her Lily knew it was her child, her Harry. Already he was so magical. Already she could see his quick and curious mind growing into the world around him. But it was more than that, a pull of some kind, like the Greek ananke , the inexorable press of fate. 

Lily knew. 

And she prepared. 

The Headmaster suggested the Fidelius Charm. It precluded the use of any other wards because such was interpreted as imperfect faith in the Secret Keeper, and for that reason Lily had initially dismissed it, being too pragmatic to place all her eggs in one basket, as it were. But James agreed with the Headmaster and he insisted and in the end that same pragmatism bade Lily acquiesce. They cast the Fidelius and Sirius Black of all people was made Secret Keeper. 

“I won’t betray you,” he said to James that night, all of them still sweaty and pale from the ritual. Marney poured everyone firewhiskey (including herself, in the acorn-sized glass cup James had transfigured for her) and Lily knocked hers back in one go. "I'd die first."

"Merlin help us, I believe you," Lily said into her empty glass. Marney took it for a refill. 

Sirius grimaced. "Look, Evans—Lily—I know we haven't, uh, always gotten on, but… er, I just wanted to—I'm sorry. For… being an arse, and… saying all that shite about you, er, just trying to come between James and me."

Lily snatched her fresh glass out of Marney's hand and sent its contents the way of the first. Then she turned a baleful glare on her idiot husband and his idiot friend. "You know I could see James gesturing at you, right?"

They both grimaced. 

"Oh my God. Marney, please."

"Yes, Miss Lily," Marney said, snatching the glass. "Men be so tiresome."

"I know."

"No, really, I am sorry." Sirius finished his drink and held the glass out to Marney. "It wasn't… fair. I was a dumb arsed kid and I thought… but this is war, y'know? Guess that would make anyone grow up some."

"Well," Lily sighed, "Harry vanquishing You-Know-Who isn't as shocking as you getting your head out of your arse."

There was a beat of silence, and then Sirius hooted with laughter. 

"I'll drink to that!" said James, lifting his glass. They all toasted and drank, even Marney, and for just a moment there was no war, no world of horrors waiting outside the door. 

But of course the horrors were still there in the morning. Lily woke up and slipped out of the bed, leaving James to snore in their rumpled sheets. Sirius was passed out on the sofa: she charmed the blankets back over him and went into the kitchen, where Marney waited with their morning tea.

Lily enjoyed her cup in silence that Marney seemed glad to share. They sipped and sighed until the tea was gone and Lily said, "I'll be needing the special library trunk today, Marney, please."

"Yes, Miss Lily." Marney hesitated. "In the Miss's study? Or…"

"In the garden shed." James wasn't fond of gardening and wouldn't question Lily spending the day out back. He had a mission today anyway, if memory served. Lily could put Harry in the enchanted swing with his hippogriff mobile and work. 

The Fidelius was strict, but there were plenty of things Lily could do that wouldn't count as wards. 

She glanced at her tea leaves and grimaced. 

Best hurry, then. 

Time was running out. 


The definition of wards per the Fidelius, which had been invented in 1582 by a tribe of Inuit mages, turned out to not be very clear at all. Said tribe hadn’t had anything like runic war-wards of the kind popular in ancient Rome and thus most of modern Europe. However, Lily was able to determine that wards required a bounded object to protect, usually a symbolically enclosed plot of land; and that some scholars considered occlumency and other personal protective magics to be a separate branch of wards, rather than an entirely different aspect of magic. The runic basis of a personal protective enchantment was necessarily very different than that of a homeward but after a week or two of intensive study Lily was inclined to agree that it still counted, magically speaking, as a ward. 

Which left her in a bit of a dilemma. She could not personally ward Harry or herself, as they were covered in the Secret — “James, Lily, and Harold Potter live at 17 Whorthwaite Lane, Godric’s Hollow, England” — and the Fidelius wouldn’t permit any wards that offered redundant protection. She and Harry were protected by the Fidelius, ergo— 

Lily moved to the subject of time-delay wards next. A passive enchantment that sprang into action upon a particular event, i.e. her own death, or James’, should not cause the Fidelius to fail; but the problem with those was power. Most spells were powered at the moment of casting. Time-delay enchantments worked best on a ley line, or even better, a ley nexus, where ambient magic was high enough to power them. 17 Whorthwaite was nowhere near a ley line, let alone a nexus of several. 

Several research projects for the Order—Death Eaters’ curses; Voldemort’s unsettling durability; advanced combat magic—took up much of her time, though they also provided a useful cover for the hours Lily spent poring over books that oozed malice. It was in one such book that she found an answer, though, after four months. 

A willing blood sacrifice, to power the time-delay protections at the moment of activation. 


The Secret was worded thus: James, Lily, and Harold Potter live at 17 Whorthwaite Lane, Godric’s Hollow, England . The critical words, Lily determined, were and and live. 

If at any point they did not all live at 17 Whorthwaite, the Secret would no longer be true, and the Fidelius would fail. 

The moment James or Lily died, Harry would be without his one great protection. 

Lily set about the spell with single-minded intensity. She vanished into her garden shed for hours at a time, emerging hard-eyed and in need of a shower thanks to the reeking magic that emanated from the books she kept there. Only when Sirius and Peter started teasing James for the visible scratches and bite marks on his neck and shoulders did she realize she ought to tone it down. 

Protecting Harry like this—she couldn’t tell them. The only person in her life who would have understood was lost to her. It was a secret Lily would take with her to her grave that she crept into the nursery at midnight every night, wrote sowilo on her son’s forehead with a finger, and breathed the Old English incantation into the quiet nursery like an offering to a forgotten god. And every night she felt the magic bind them more tightly. 

She carved runes into diamonds and placed them around the house: so long as her death occurred here, in the plot of land owned by the House of Potter, of which she was a member, the runestones would turn her willing sacrifice into power. On every full moon she slipped out to smear fresh blood on each of them. On the mornings after she was every bit as haggard as Remus. 

It was forgotten magic. Soul magic. The Killing Curse was a soul violator, and the only thing Lily could do against Voldemort’s most feared instrument of terror was bind her son’s soul in his body; and the only way to do that was to sacrifice the sanctity of her own. 

She would stand between her son and Death. She would let her soul be shredded, never to reincarnate, if it would keep her son safe. 


Lily stopped leaving the cottage even to visit friends. James chalked it up to wartime paranoia. 

Sirius did not. 

“You shouldn’t be mucking around with this,” he said, holding a stack of books she’d requested from the Order resources for research. 

Lily just laughed and summoned them into her own hands with a smack. 

Sirius blinked. She was not holding a wand. 

“I’ll muck around with what I want to,” she said.

“Don’t think I haven’t noticed you never leave anymore. Got any little runes hidden away? Granite, maybe? Cotswold stone?” 

Lily fixed him with eyes the color of the Killing Curse and said, “Sirius Black, if you think to stop me protecting my son in every possible way, you had best think again before I make you.”

“Sometimes I think you’re a Black from the wrong side of the sheets,” he muttered, but he was looking away, backing down. “And shouldn’t you say our son? He’s James’ too.”

“Yes,” Lily said. “Of course. Our son. How silly of me.” 

James didn’t notice how Sirius avoided her after that, either. 


The boys came to Godric’s Hollow with an insane, clever plan. Perhaps too clever. Lily rocked her sleeping son while in the living room Sirius and Peter argued with James. 

She had never heard shy, sweet Peter this assertive. He spoke up around that unfortunate stutter and insisted that he could do it, he wanted to do it, he’d die for them like they would for him, and anyway it would keep them safer this way, hadn’t Sirius already been targeted time and time again because You-Know-Who thought he knew where the Potters hid? 

James agreed. Lily, desperate to do anything that would keep her son safe, even paint a target on Sirius and damn Peter to months of fear, agreed.


Death came to Godric’s Hollow on October thirty-first. Lily had to hand it to Voldemort: his sense of dramatic timing was impeccable. 

She was on her knees under the crib, drawing runes in her own blood, when she felt the Fidelius fall and knew James was dead. She did not weep. There was no time for weeping. There was no time even to wish horrible, painful death on Peter: Lily was busy rising, deepening the gash on her hand, and redrawing the rune she had placed so many times before, this time in blood on Harry’s forehead: sowilo , the embodiment of victory, triumph, power. 

“May you be powerful enough to triumph over all who would harm you,” she whispered, a last benediction, and still she did not weep as she kissed him one more time. 

The door blew open. Lily Potter turned to meet her fate.