The frost fair came to Arendelle once, when Anna was a young child. The winter that year was so severe that for the first time in living memory the fjord froze over. A great fair was erected there. That was when the gates were still open, and her father had carried Anna on his shoulders through the fair. She and Elsa ate jellied eels and candied apples and lost at skittles.

Having passed through the Mirror, that was the sight that greeted Anna: the frost fair of her childhood.

A sea of striped tents stretched across the ice. The sound of laughter, calliope from the organ, jugglers performing tricks, stallholders shouting. The smell of roasted chicken and sickly sweet sugar tickled nostalgically at her nose and her heart clenched, painfully, as she was dragged back to that day.

If what Ada said was right, this was Elsa's heart, and therefore… this is one of her memories?

Except there seemed something off about it.

There's… no people.

Calliope sung sweetly and children laughed but there were no children, no winder to wind the organ. The breeze moved the debris of the fair, napkins littering the ground and a forgotten silk shawl, stirring ghostly, and the little boy's laughter in the distance took on an eerie tone.

"Roll up! Roll up! Get your tickets here!"

The call came from a ticket booth, a small erect tent the size of a Punch and Judy show. Anna approached curiously, fully expecting to see no-one, and so was surprised when she looked down and saw a tiny little baby snowman, dwarfed by the chair he was sat in.

"Oh!" she said in delight. "Are you one of Elsa's snow creatures?"

"Do you want a ticket or not, lady?" the snowgie squeaked, perusing slowly through a huge novel with tiny little arms.

"A ticket for what?"

"For the tour," said the snowgie. He sounded quite bored.

"What kind of tour?" asked Anna.

Boredly, from rote, the snowgie repeated, "'A Frozen Heart.' A mesmerising and intriguing trip through the heart of Queen Elsa, Queen of Arendelle."

Anna blinked, and then made the decision that it would be best just to roll with it. "Yes please, then. One ticket."

"One second," said the snowgie. "Lemme check the list." He scrabbled with his little arms for a heavy guest-book and scanned through it. "What's your name?"

"Princess Anna."

The snowgie scanned through the book, flipping over a few pages, and said, "Sorry lady. You ain't on the list. I'm afraid this is a very exclusive tour."

"No way!" said Anna, leaning over the ticket booth. Just as the snowgie had said, her name wasn't on the list. But, nor was anybody else's.

"Hey!" she said. "That guest-list is empty!"

"Like I said— it's a very exclusive tour."

"What on earth is the point of running a tour if you don't let anybody on it?" Anna huffed.

But then the snowgie found the memo tucked in between the pages. He exclaimed, "Well, well well! Isn't it your lucky day? I've got a note from the boss; you've been made a VIP visitor. Our first ever, actually."

"The first VIP?"

"The first visitor," said the snowgie, handing her over a badge to pin to her apron. It read:

Princess Anna of Arendelle

VIP

"The boss you mention… that's Elsa, right? Do you know where I can find her? It's very important." She had no doubt that once she found Elsa, this fault in the Mirror— whatever it was— was sure to be nearby.

But the snowgie just waved her towards a blue and silver striped tent. "The tour guide is waiting for you inside. Don't keep him waiting." He went back to his brick of a novel, completely ignoring her.

How rude, Anna thought. But perhaps the tour guide would be more helpful.

She parted the entrance to the tent and went inside.

But she found no tour guide waiting for her.

Instead, she found a child's den built under a fort of blankets. The closer Anna got, the more familiar it looked, until she noticed the blue blanket, sewn with tiny stars, and gasped and snatched it up, exclaiming, "Hey! That's my old blanket!"

Revealed inside the den was a magpie's hoard. Except, if the magpie had gone out collecting toys instead of shiny things.

"My bear!" said Anna, adding it to the growing pile in her arms. "And those are Elsa's blocks. And hey, that's my doll—" But as she pulled at her old Princess Elsa doll (her sister owned the counterpart) she found it wouldn't come free. Anna pulled harder, bracing her legs back. It seemed to be attached to some stick thing.

With one last heave, Anna pulled, and the doll came free. Along with the thing attached to it. Anna hit the floor. She stared at the striped roof of the tent, winded. Something heavy was lying on her chest. Something cold.

Anna pushed herself up on her hands to see…

"Olaf!" she exclaimed. The little snowman was fast asleep on her, still stubbornly holding on to her doll. He'd apparently fallen asleep under the pile of toys. Anna shook him. "Olaf, wake up!"

Olaf jerked awake with a snort. Eyes widened with joy and recognition. "Heee—ey, Anna! What are you doing here?"

"I could ask you the same thing, Olaf! Not that I'm not glad to see you— because I really, really am. But, what are you doing here? And what are you doing with all that stuff?"

"I live here!" Olaf said, beaming. And he gasped, covering his mouth with his stick hands. "How rude of me not to invite you in." And with that he climbed off Anna and waddled inside the blanket fort. "Please, come in. Come in!" he called jovially from inside.

This was going to be a tight squeeze. Shrugging, Anna crawled into the fort on her hands and knees, hoping to find somewhere at least to sit.

"Huh," she said.

"Welcome to my house, the Childhood Imagination Room," Olaf sung, stretching his hands to the huge space around them. She'd barely fit through the gap in the blanket fort, but now she stood with several foot to spare. They were in a child's wonderland. There were mountains of pillows and toys and a swing that hung from a ceiling. There were all sorts of toys and nick-knacks from her and Elsa's childhood that she hadn't seen in years. The wooden toy boat Kai built for them. The pull-along goose. Anna couldn't help but beam as she ran her fingers along the china doll she'd adopted as a little girl. She hadn't thought of her in so long.

"This is amazing, Olaf!" Anna could feel the huge grin straining at her dimpled cheeks.

"If you like this, you'll love what what we've got planned next. You haven't seen anything yet!" Olaf said, literally bouncing from excitement. "I haven't been able to give a tour in, gee, I guess ever. I've got so much to show you."

"You're the tour guide?"

"Yep!" Olaf said, puffing up his chest like a proud penguin. There it was, pinned to his puffed chest: a brass badge engraved with the words:

OLAF

snowman/ tour guide

"I know all about Elsa. She made me, you know?" Olaf confided, bubbling under the surface like a kettle on the boil, bursting with pride and excitement.

"I know," said Anna, smiling. He seemed so pleased with himself.

"Let's get the tour started!" Olaf said, tugging at her arm. "Or we'll be late!"

The door from the Childhood Imagination Room led out into Elsa's ice palace. They stood in a long, icy corridor, lit by lights from overhead chandeliers that refracted all over the place in a prismatic rainbow.

"Where are we?" said Anna.

"Elsa's subconscious," said Olaf, the way anyone else might say, 'the sitting room.'

The corridor was lined with dozens of doors, each of them labelled with a child's young, wobbly handwriting. Anna scanned them as they walked past. She saw 'The Repressed Memory of the Ice Cream Incident Room', 'Smells Familiar Room', 'That Thing That Lived Under Bed Room,' and the 'Books I Forgot to Read Room.'

As they walked together, Olaf provided an excitable, leaping, bouncing, gambolling commentary.

"And that's where we keep all our smells. All the nice stuff like freshly cut grass, and oooh, chocolate. And all the not-so nice stuff, like that mildew smell that gets into the west wing when it rains. Nuh-uh. And—"

"What exactly is the point of all of this?" Anna asked. She couldn't figure out why on earth Elsa needed rooms in her heart like paper airplane ideas or the sound toast makes when you scrape the burnt bits off.

"There isn't so much as a point, per say," Olaf said with a cheerful shrug. "It just is. We're on the periphery of Elsa's heart, so these are just old memories and feelings she doesn't think about much. When they're forgotten, the renovations crew comes and sorts through them and chucks the old stuff out to make way for new memories."

"The renovations crew? You're not the only person here, Olaf?" Anna asked.

"Course not! With a heart as large as Elsa's, we need a whole contingent of staff to keep everything running properly. And this is just the outer part. All of Elsa's important memories are further in."

Further in. That had to be where the fracture was.

"Is that included on the tour too, Olaf?" Anna asked.

"Ahh, well actually, it's uhm, closed for renovations right now. They're, ur, putting in some new mood lighting."

Anna narrowed her eyes at Olaf. He was shuffling his foot in a very nervous manner. "Mood lighting?" she asked, arching one eyebrow.

Olaf, Anna thought, looked very much like a small child caught doing something wrong. "Ur…"

"Olaf, come on."

Taking a deep breath, Olaf said, far too quickly for Anna to catch anything, "Elsakindofmighthavelockedtheheartdooranditkindofmightbeallmyfault."

"Say that again."

This time Olaf mumbled so fast Anna only made out the words Elsa and a high-pitched squeak.

She held back a sigh. Hands on her hips, Anna pulled on her best Elsa-like royal voice. "Olaf, I command you to stop mumbling and tell me what on earth is going on this instant."

Olaf only hesitated a few more seconds, before the dam broke, and he bewailed, "I'm sorry, Anna. It's all my fau—ult!"

Well, apparently that hadn't been the best approach. She knelt down beside Olaf, ignoring the cold of the ice floor clambering through the material of her skirts and petticoats and put her arm around the snowman. "Please calm down, Olaf. Whatever it is, I'm sure it'll be alright."

"But Anna, you don't even know what I've do—ooone," Olaf moaned, covering his eyes with the twigs that served as his hands.

"Whatever it is, Olaf, I'll help you fix it," Anna promised him, rubbing slow circles on his back.

He shifted one twiggy hand to peek out at her. "You will, Anna?"

"Of course I will. We're friends, aren't we? So we help one another."

Somewhat consoled, Olaf moved his hands from his face, and prodded two twig-ends together nervously. "I might not have been telling completely, 100% the truth when I said you were the first visitor," he said in a low, breathless, wide, guilty-eyed confession.

"Someone else was here?"

"She didn't have a badge, but she seemed so interested, and I'd always really, really wanted to be a tour guide, so…" he prodded his twigs together again.

Anna was starting to figure out where this was going. "Her name wasn't Ada… was it?"

"Oh, heeeeey, that was her!" he said, the lightning flash of excitement quickly slipping behind overcast clouds. "Um. So I might have given her a tour. And maybe shown her Elsa's memories. And maybe given away her secrets. Maybe. By accident!" he swiftly clarified.

Well. That certainly explained how Ada had been able to blackmail her sister, didn't it?

But she couldn't bring herself to blame Olaf. He was as trusting and innocent as a child. In a way, he was trust and innocence- Elsa's trust and innocence crystallised into a living creature. "It's not your fault, Olaf. You were tricked. I know you would never mean Elsa any harm."

But Olaf was still awkwardly prodding his fingers together. "You've not heard the worst of it. When Elsa heard what happened she was furious. She blew a huge snowstorm, like, whoooosh! And she blew the gates closed."

"The gates?" Now that sounded familiar.

"The gates to her inner heart. And they've hardly been open for six months…"

Six months… "You mean since Arendelle was thawed?" Anna asked.

"Yes! And it'd been so nice. We'd all been together, laughing, playing, with all the doors thrown open wide… until…" Olaf hiccoughed, "until I went and ruined it!" He'd gained some measure of composure up until now, but now he dissolved back into tears. Anna's hand went back to rubbing circles.

"Come on now, Olaf. You'll turn into a puddle if you keep crying like that," she admonished him. "I told you I'd help you, didn't I? We'll find a way to open the gate, and then you can apologise to Elsa and everything will be fine."

Olaf sniffed, loudly. "Okay, Anna."

"I'm going to need your help though. This is your world, not mine. Now, I bet you know everything about this place, especially since you're a tour guide…"

Olaf chucked wetly, and with an air waved this away. "Aw, I don't know about everything…though…"

"Though?" Anna prompted him.

"Well, I do know of somebody who could help us get further inside. But…" he faltered.

"But what?"

"But Elsa locked her away long ago. Nobody has seen her in years. Said she couldn't stand the sight of her and shut her away in the maze." When Anna asked, what maze, he expanded, "The maze in the frost fair."

An old memory bobbed up to the surface like a bottom-feeder drifting up to nibble at a crumb. The house of mirrors at the frost fair. How she and Elsa had got so lost in it, laughing at the distorted reflections of themselves, smacking into panes of mirror-glass, laughing, hands joined like a string.

And then Anna emerged from the memory and she was running, dragging Olaf behind her by the arm like her pull-along goose. Back down the corridor; through Olaf's room; back into the starry night and the calliope and hissing gas lights of the frost fair.

The sign above the tent read, The Castle of Illusions.

Inside, they'd become separated. Had bounced off the glass, laughing. "Anna, I can't get to you~" The memory was so vivid, it was almost like she could hear Elsa's voice in her head.

Anna parted the tent flaps and strode with purpose into an antechamber lined with mirrors reflecting back comical distorted images. The maze was ahead.

"An~na, wait, slow down!" she heard Elsa laugh, and it wasn't as though she could almost hear Elsa. She really could hear her.

"Elsa?" she shouted.

Olaf's hand closed round her wrist. "Anna, it's dangerous in there," he said, in wide-eyed fear. "Once you go in, you might not ever find your way out."

Gently and patiently, Anna pulled Olaf's hand away and clasped it. "Wait here for me. Okay, Olaf?"

"O-okay. But be careful."

Anna strode into the maze. Countless Annas stared back at her. Reflections of reflections of reflections.

She froze, however, when she noticed that not all of them were the same.

There she was, confused eyes regarding herself, the shadow of the bruise the brutish guard had given her pickling yellowish under her eye socket, hair unwinding from its bun, a thread from her apron coming loose and run in her stockings.

And yet, there she was again, in her winter dress and cloak, determined eyes boring back into her own. And again, in the gown she'd worn to her sister's coronation, eyes wide with hurt. The echo of it ghosting against her eardrum: "What did I ever do to you…?" Grinning in her nightgown. Smiling in her favourite summer dress.

Disorientated and stumbling, Anna spun round to find her fifteen year old eyes gazing back at her, brimming with tears. In black. Dressed for mourning. "We only have each other, just you and me."

"An~na, An~na, come and catch me~" her sister's voice sung.

She caught it out of the corner of her eye: little Elsa, skipping out of sight. Anna swung round, coming face to face with herself, five years old, offering up a baleful look. "Elsa… why don't you want to play with me? Don't you like me anymore?"

"Elsa!" Anna called. "Where are you?"

These must be memories of me, Anna thought. Elsa's memories of me.

Intense eyes staring back through the slits of her antique butterfly mask. When she moved, her white-silver, gossamer dress danced around her like air. It was the outfit she'd worn to the masque ball, and yet Anna had never seen herself like this before. The dress had pinched, had clashed against her hair, and hadn't sat right on her shoulders and yet…

The creature that looked back at her with flashing, forest eyes, such a deep, deep green was divine. "I want to meet you." She looked nothing at all like Anna, but…

Because… this must be how Elsa sees me.

"Come on, Anna! Are you coming to get me or not?" Elsa called, vanishing.

Heart clenching brightly, painfully, Anna called out, "Where are you, Elsa?"

A giggle and, "I'm here!"

Anna extended her hands and started to walk, feeling her way forward so she couldn't hit the glass, face-first. "Where's here?"

"Not that way. This way!" Elsa called.

"This way?"

"No. That way!"

"Left?"

"Right."

"Right here?"

"No, silly. I meant you were going the right way!"

Annas behind Annas behind Annas.

How lonesome it must be to be trapped here, facing everyday only yourself and your own flaws.

She said, "Don't worry, I'm coming!"

When she turned left, the Anna in the mirror turned right. When she went right, the other Anna went left. Dizzying, disorientating, she kept going, even when there was no way of knowing where she was going. Just when she caught sight of half of Elsa in the mirror, she would head in that direction and lose her completely. She chased the flashing, mirage tail end of a blonde braid as it whipped by, and in her hurry smacked face-first into the glass with a crippling whack.

Right; left; left; left, right! Anna felt like she was chasing a vanishing, giggling illusion ("You're so slow, Elsa, come on!") and she swallowed down the warning Olaf had given her about being trapped forever. She would get to Elsa. She had to.

And then Elsa was there, right in front of her. No more than eight years old, her hair French braided, in one of her favourite blue dresses, stretching out her arms to her. And Anna was hurrying forward, to snatch up her sister before she could vanish, and—

SMASH!

She hit the glass hard, and it shattered with a sudden violence. Bright, white lights resounded in her head. When she came to, she heard Elsa's voice: "Anna? Anna, you're bleeding. Are you okay?"

Though she'd hit the one pane, the entire complex of mirrors had smashed into smithereens. It lay on the floor in sharp tiny shards of glass. Like slivers of ice.

"I'm fine," said Anna, though it was hissed through her teeth. She touched her temple, and when her fingers came away they were spotted with inkblots of blood.

"Thank goodness," sighed Elsa. Except that—

Her voice was coming from the inside of a conch shell.

Anna pushed herself up off the floor, swallowing down sudden vertigo and nausea, and asked, "…Elsa?"

"I'm in here," said the voice from the shell. Anna thought it sounded a little embarrassed.

The conch shell sat on a child's wooden stool, one from Elsa's old room. Anna picked it up. It was white and very smooth. She peered into it and called, experimentally, "Uh, hello?"

When she put it to her ear, the voice that came back was louder, as though Elsa was standing right next to her. "Anna. You've no idea how glad I am you're here. Wow, you've gotten big."

"And you've… ur, gotten more… smaller," Anna said lamely. Out of curiosity, she gave the shell a shake, and there was a scraping sound like something large and wooden sliding, followed by a big crash. "Whoah, Anna, watch out for the furniture! I nearly got crushed by the wardrobe."

W-wardrobe?!

"Sorry!" she said. There was a heaving and scraping sound, presumably as Elsa righted the wardrobe. "How on earth did you get in there?"

"She—" the word was spat like poison, between pants of exertion, "—put me in here."

"She?"

A resigned sigh. "Oh, alright. Me. The me you know. The me from the future, but definitely not me, because I'm nothing like that coward."

The resentment and vindictiveness in her kindhearted sister's voice startled her. It was a tone Elsa only used when she was talking about Hans, or occasionally people that wasted chocolate. "You don't sound like you like her… uh, I mean, you, very much."

"That's because I don't. She put me in here. Locked me up and hid me away. Just like our parents did to us."

Olaf ran towards them over the powdered glass, waving excitedly his little knobby sticks of arms. "Anna, you did it!" he gushed. "And Elsie! There's something about you that's different, though I can't put my finger on it… " he mused on this, finger to his chin. "New haircut…?"

"Olaf!" the voice in the conch exclaimed. "I was afraid she might have locked you away too."

He shuffled nervously. The kid whose hand was caught in the cookie jar look again. "I'm sorry, Elsie. I wanted to come find you, but the Queen forbade it."

Elsa humphed. "She would," she said, before adding quickly, "But it's not your fault, Olaf."

"Elsie—" the childhood endearment tripped off Anna's tongue effortlessly, "there's something that I need your help with. I need to get to the centre of this place. The problem is—"

"She's gone and locked the heartgate again, hasn't she?" Elsie sighed.

"Do you know if there's any way to open it?"

"I know a way. It's my heart too, after all."

"Then you'll help us?" Anna said.

"Of course!"

A loud guttural rumble shook the earth, and the ground beneath their feet began to tremble. Carousel horses creaked and gas lamps wobbled.

"Uh-oh," whispered Olaf, hunched into himself, voice a frightened murmur. "She knows we've let you out of the maze."

Anna could laugh aloud at the absurdity of it all. They were frightened? Of Elsa?

"I'm not scared of her," Elsie announced proudly, though Anna detected a slight waver in her voice.

Olaf's hand caught around her wrist. "We should get out of here. I'll take you to the heartgate, Anna."

They were running now, the conch shell clamped carefully in her hands. Ducking under the purple and gold striped tent, emerging in another ice-crystal corridor. Something she hadn't noticed before: this didn't look like anywhere in Elsa's ice palace.

In fact, it rather resembled the east wing of Arendelle Castle.

By the stairs to the servants quarters, they stopped for breath. The rumbling had stopped, and Elsie said, "We'll be safe here, for a little while."

Sucking in deep breaths, one hand pushed against her thighs, Anna thought that she hadn't got this much exercise since she last climbed a mountain for Elsa. What was it with her sister and rigorous physical exercise?

"Okay, so it's alegbra lessons when I was seven, right?" said a gruff voice. She pushed herself up straight to see two little creatures like the one she'd met at the ticket booth rounding the corner, wheeling along a stepladder that ran on a runner against the wall.

"Oh yeah, who needs those anymore? Chuck 'em," said the other little snowgie, flicking through the pages on his clipboard.

His colleague bounced up the stepladder and pulled out the brass name plaque above the door, tossing it into a growing pile in the sack at his feet.

"Hey Flurry! Hey William! How's it going?" Olaf skipped up to the snowgies, who paused at his excitable approach.

"Oh, hey, Olaf. S'alright. Queen's got us working some serious overtime, though."

This must be what Olaf was telling her about earlier. Memory renovations. Well, to be fair what use is algebra to anybody?

The two little snow creatures were a quick and efficient team. In no time at all they were pushing the ladder down to the next door, Flurry enquiring, "The night at the masque ball?"

"Get rid of it," said William, flipping through his clipboard. Flurry hopped up the ladder, and just as carelessly as he'd done with the alegbra lessons, he chucked the memory of that night into the sack.

Anna marched up to the snow servants. "What on earth do you think you're doing?" she demanded.

"Memory renovation," said Flurry, without interest. "Hey, William, what are we replacing it with?"

"Hm… a quiet family dinner with Ma and Pop, apparently. Here," he threw him the new plaque and Flurry slid it in.

With Ma and Pop…? But that doesn't make any sense. That was only a month ago.

"What are you doing to do with the old one? And all of those?" Anna said, stabbing a finger at the bag.

"Oh, they're all slated for the incinerator," William said.

"How come you've doing so many, William?" Olaf asked.

"Worlds-a-changing and we've got to change with it. Gotta take out all of these sad memories and all that stuff from the past month's gotta go, too."

"But you can't take those!" Anna exclaimed. "If you do that, then…" Then all that stuff that happened there will be gone. The good and the bad. All the evenings they spent together. All the things they'd shared.

"I don't give the orders, sweetie. Got a problem? Go see the Queen," Gary said, as they dragged the ladder. Replaced the plaque that read, my conversation with my sister in the maze, replacing it with, chess with Dad.

He chucked the plaque into the pile like it was trash.

"The fool," muttered Elsie from the conch.

No! I won't let you take even one of Elsa's memories! Anna snatched up the sack, throwing it to a wide-eyed Olaf so she could carry Elsie safely.

"Whoah! What are you doing, Anna?" Olaf exclaimed.

"Come on!" she said.

"Hey, give those back! Those are the property of her Majesty Queen Elsa!" Gary said, but by then they were running, Anna dragging Olaf behind her as a shrill whistle sounded, and Flurry yelled, "Backup! We need backup!"

They were running down the corridor now, out onto the landing as a cascade of snowgies exploded from a door behind them, blowing whistles and shouting to cease, halt, desist. Anna didn't stop, dragging Olaf who lagged behind her like a heavy cannonball, shouting, "Hurry up! Hurry up! Hurry up!" The snowgies were like an avalanche, tumbling down the corridors now, a white, terrifying, growing mass.

"Stop!", "Come back!", "In the name of Her Majesty, desist immediately!"

"A—Anna, a-are you sure this is a good idea?" Olaf gasped.

"Come on," she said.

They were at the grand staircase, hurtling up the stairs, a stitch burning through her, the back of her calves screaming. Down another corridor, and another, and—

Only to find a barricade erected, manned by two dozen snowgies, barring the way. "This is your last chance. Return Her Majesty's memories immediately!"

"This way— this way," said Olaf, and with no other choice they tumbled through the door to their left, chased by the pervading, ringing shrill whistle.

—Out into the bright, startling light of Arendelle Castle's courtyard, where Anna felt a cold shock impact against her face. Stunned, she brushed off the remnants of the snowball. Her hands, she noticed, were rather smaller and more chubby than she remembered.

A merry gurgle of a laugh. "Come on, Anna! You have to do better than that!" Elsa emerged from behind the bench, mouth split open in a grin, bouncing another snowball in her hand.

The words were out of her mouth before she realised she was saying them: "Nuh-uh! Gonna come get you, Elsie!"

Then she was compacting cold snow in her childish hands, and they were laughing, shouting together, flinging snow and running, snow flying everywhere. Until Olaf's hand clasped her own. She was small enough now that their eyes were level.

"Come on, Anna. You can't just play in Elsa's memories all day. We have to find the heartdoor," he reminded her.

"…Kay," she huffed in acquiescence. "Buh-bye, Elsie!"

Elsa waved, dress powdered white with snow. "Bye, Anna! Let's play later." She threw one more snowball for good measure. Olaf pulled Anna away before they could recommence their snowball fight, out through another door.

The shrill whistle was behind them again and they were running once more, Anna racing as fast as she could on her short little legs, clutching the conch to her chest, breathing hard and shrieking with the excitement and terror of the chase. They tumbled into memory into memory into memory. Past the table in the dining room laden down with treats for Elsa's sixth birthday, tumbling head-first through a door down the grassy hill with Elsa, cartwheeling, laughing, falling into—

Darkness.

The curtains were drawn, sunshine escaping in a thin golden band drawn down the gloom of Elsa's bedroom.

A soft hiccough of a sob.

Elsa's nine-year old eyes, icy teardrops clinging to matted eyelashes, looking up in confusion. Legs pulled up to her chest, she hunched with her back pressed up against the door. Ice streaked up in a glittering cobweb around her.

"A-Anna?" she hiccoughed. "H-how did you get in here?"

Feeling welled up in Anna's chest, the motion difficult to pronounce with a six-year-old's tongue.

"It'll be okay, Elsa," she said, reaching out to take Elsa's hand.

Elsa looked at their joined hands- their threaded fingers- in confusion. And quite abruptly, pulled her hand away, cradling it to her chest. "Anna— don't. I— I'll hurt you. You're not even supposed to be here. I'm not allowed to see you anymore." Her voice broke with emotion like a flint snapping in half, and she covered her eyes with her hands.

It hurt. It all hurt so much. Even after all this time.

Grief and anger was a tight stopper in her throat, and Anna had to force the words. "I promise," she said, tight and nasal.

"A-Anna…?"

"It'll all be okay one day, Elsa. I promise. We'll see one another again. It's not your fault, so don't cry. It'll be alright."

Elsa's wide, uncomprehending eyes, blinking away diamond tears. "Anna, I don't…"

"It'll all be okay, so—- just wait for me, Elsa," she said, almost shouted, as she tore herself away from the scene, reaching blindly for the exit, eyes burning with tears. She stumbled out, into the brightness of the unnatural ice corridor.

And stared up at the giant door that towered overhead.

It was massive, towering so tall that craning her neck with a crick, Anna still couldn't see the top of it. Embossed, of course, with Elsa's signature snowflake.

"Anna, wait up—" Olaf panted, slowing to a trot beside her. "I think we lost 'em. Are you… are you okay, Anna?"

Anna grabbed Olaf, hugging him so tightly enough to compact the snow-stuff he was made of. "It's just not fair," she said, voice muffled into his shoulder.

"We should get going, before they catch up with us," Elsie said from the conch. She sounded deeply weary.

"It's no good, anyway," Anna sniffed. "There's no way we can get past this. We don't have the key. Elsa's not going to let us in. She never has."

"Anna, check your pockets," Elsie said.

Pulling away from the snowman, wiping her nose on her sleeve, Anna dug in her apron pocket. With her fingers— adult fingers, she only noticed now, the transfiguration of the memories losing their magic on her— she dug out something hard and metal.

Anna opened her palm to find a small, brass key, marked with a snowflake, as though it'd been in her pocket all along.

To be continued.