(A/N) There's a crack theory floating around Tumblr that this season's Caitlin is not our Caitlin, but a doppelganger Killer Frost from another dimension, an old enemy of Jay Garrick's who'll make life interesting around Star Labs (like they need it). I couldn't stop thinking about it, and this came spilling out.

Y'all, I had so much fun writing Louise, you don't even know. I've never read the comics so she is probably nothing like the original. I just liked her name the best.

Depending on what the show does, this may not be the last you see of her.

As Louise walked up to the front door of the apartment building, a cute guy with long black hair and a nerdy t-shirt was just coming out. He held the door for her, and she grabbed it with a nod.

He did a double take and frowned a little, but she kept walking without even taking off her sunglasses. She was pretty sure who that was, and she was equally sure she didn't want him knowing she existed until she was ready.

The door to 4-C was unlocked, so Louise let herself in.

Caitlin rushed out of the kitchen. "Cis - oh."

"Expecting someone else?" Louise walked past her, tugging off her leather jacket and tossing it on a handy chair. "What are you eating?" She picked up the brand-new pint, untouched except for the spoon stuck into it. "Ice cream? Honestly, Caitlin. Why do you do this to yourself?" She rummaged through the cupboards.

"I'm out of hot chocolate. You drank it all." Caitlin picked up her jacket and carefully hung it on the back of the chair.

"Ugh," Louise said. "Do you at least have any of the good tea?"

"You drank that too."

"Are stores not a thing in this world?"

"You know they are. You could stand to go to one."

"Why should I? You have everything."

"Except tea and hot chocolate. Thanks to you."

Louise found a cup of soup, the kind you heated in its own little bowl. Oh, well. She peeled the top off and stuck it in the microwave. She plucked the spoon out of the pint of ice cream. At least Caitlin hadn't actually eaten any of it.

She licked the spoon thoughtfully. Mint chocolate chip didn't really taste the same in this world. Or maybe it was because she hadn't had ice cream in so long.

"You're eating my ice cream and my soup?" Caitlin asked, just as the microwave dinged.

"The soup is for you." Louise plopped it on the table in front of her. It splashed a little. She slapped a fresh spoon on the table next to it. "Eat. This, I'm taking off your hands. For your own good." She dug her own spoon deep into the ice cream.

"You're so generous," Caitlin said, stirring the soup. She probably didn't realize she was looking at the steaming bowl of chicken noodle like it was the ice cream she hadn't been able to touch.

"A humanitarian, in fact. So I'm guessing the famous Cisco finally dropped by," Louise drawled. "What drove him to break the silence?"

Caitlin swallowed her soup and said, "A drained radiation tag. From a body that was almost the twin of the meta who showed up at the rally. Did you see that?"

"I don't see how anybody could have missed it."

"Anyway, Cisco came to Mercury today and asked me to look at it. Check to see if it was damaged. If there was something to account for its complete lack of radiation. I asked him to come here tonight to learn what I found."

"He couldn't do the tests himself?"

Caitlin shrugged. "Mercury has better equipment than he has access to right now."

Sure, Caitlin. Pretend you believe that. Louise scooped up more ice cream. "What did you find out?"

"Nothing. There was nothing to account for it."

"Except an outside force." Louise's brain whirred through the possibilities. "Do you still have it?"

"I gave it back to Cisco."

Well, damn.

"Louise, of all people I know that metas in this world are still developing. But is there a chance - " Caitlin took a breath. "Could that meta have come through the same breach you did?"

"Maybe. Hard to say. Who knows how that breach worked. But he seemed pretty mayhem prone, from what I saw on TV. I don't think he could have kept quiet for five months." Louise licked the spoon and cast around for a proper distraction. "So. I think I passed by Cisco outside. Long hair? Shirt with little lightning bolts?" At the other woman's nod, Louise grinned. "Tell me you hit that. At least once."

"Cisco?" Caitlin's voice squeaked. "Of - of course not. He's my friend."

"What's a little good natured sex between friends?" She pointed her spoon. "And you know the thing about the guy who's not a movie star? When you climb on that, boy do they make sure you're going to come back for seconds."

"No, Louise," Caitlin said firmly.

"It's a waste," Louise said. "Is all I'm saying."

As she'd figured it would, that thought flustered Caitlin so badly that she huffed and concentrated on her soup, leaving Louise some space to think.

A body, and then a meta that was its twin. Well, that didn't sound good. If that meta had been from her world, or another, then it meant that the breach she'd leapt through wasn't the only one. She'd seen it open, seen it close, and been convinced that she was stranded.

But what if she wasn't?

And what if she wasn't alone?

The universe (multiverse, apparently) sucked, so odds were good that it wouldn't just be some mayhem prone metas that landed here. With her luck, it would be the two men she wanted least to see.

Zoom was bad news, but he was at least predictable. A megalomaniac who needed constant reassurance that he was the best. Louise had dated a couple of guys like him. As long as she stayed behind him, and occasionally did a favor, he left her alone. (When he didn't was when it was a problem. But no, she wasn't going to think about that.)

Jay Garrick was something worse. Jay Garrick was a hero.

Square-jawed, square-shouldered, really just square all around. With a moral code like a battleship and a way of looking at you like you were a bug if you were just the tiniest bit flexible about little things like laws.

A girl had to be practical and look out for number one. Also, if a girl wanted to indulge in hot hatesex with a hero, she had to make sure to keep her face covered.

Boy, had that been a mistake.

But it had been worth it, not just because it had been really good, but because Hero-Boy was probably tied into knots over it. Louise grinned wickedly into her ice cream. God, she enjoyed mussing him up.

She avoided thinking about the other implication of open breaches. She wasn't at all sure she wanted to go back. Home. Was it home? She really didn't know.

This kind of soul-searching wasn't her thing, so Louise was able to ignore it easily.

If Zoom or Jay Garrick turned up, she was going to need a lot more security than she had right now. She'd lucked out with Caitlin, who could fill her in on how metas had developed in this world, but she was still too far from the action, from the intel. She needed to be in the thick of it.

After hearing the stories of Captain Cold and Heatwave, she'd considered seeking them out and offering her services. They sounded like her kind of people. But they wouldn't give her that security.

No, she needed to be at Star Labs - one way or another.

Caitlin had finished her soup, practically licking the bowl clean. She got up to throw the container away. "Are you done?"

"Nope. Let me enjoy this, would you?"

"Really?" Caitlin said wistfully, putting her spoon in the dishwasher. "No ice cream?"

"Not for five years." She was making up for it now. Good thing she walked so much.

"I don't know if I can do that."

"You get used to it." You could get used to just about anything, in Louise's experience.

Caitlin wandered into the other room and dropped onto the couch, curling her legs up. Louise knew a silent request when she saw it, so she followed, flopping onto the other end of the couch, propping her feet on the coffee table.

"Hey," Caitlin said without much hope. "Food belongs in the kitchen."

Louise slurped more ice cream and grinned at her. "Go ahead," she said. "Say what's really on your mind."

Caitlin stared at the blank and silent TV. She reached out, and without looking, pulled a thick, fluffy blanket around herself. "He wants me to come back to Star Labs. I know he does."

"So go back. You're bored mindless at Mercury."

"I am not! It's very interesting. Stimulating. I'm working on some - some very exciting … Just because it doesn't have crazy metas popping out of the woodwork and - and - dramatic situations every day and night, and - I'm doing good work. I am."

"You're ready to climb the walls."

"I can't go back," she said. "Not just because of all the memories." She held her hand out and watched the mist collect around her palm for a minute. She folded herself back down into the blanket and shivered. "I need to get control of this. I don't want to be the next person in the pipeline."

"I get it," Louise said, her heart suddenly thumping in her ears. "But you want to go back. I see it."

Caitlin avoided her eyes. "They need me. It's been quiet for the past six months, but if all this is going to start up again, the metas and all … I mean, they need me."

"Forget them for a moment. They got a year out of you. More. What do you need?"

"I - " Caitlin swallowed. "I need. I need to get warm."

"That's not going to happen."

"It happened to you."

"Going through a breach to another world is a little extreme, and I don't even know if that's what did the trick."

She wasn't exactly sure if she missed it. The cold had been the center of her for so long that moving through the world without it was surprisingly lonely. Maybe that was why she'd latched onto Caitlin Snow.

Snow. Honestly. This world had no subtlety whatsoever.

She dug around in her ice cream. "What about that project that Tina McGee talked to you about?"

"The one in the Arctic?"

"Can you imagine a better place? Everyone's all bundled up already. They'll never notice your cold powers going kablooey."

"Oh, please don't." Caitlin grimaced.

"Honey, be realistic. You're just starting to manage them. Of all people, I would know - kablooey is a distinct possibility. And where would you rather have it happen? There? With a tiny population? And all that warming equipment? Or here? In an urban center. So many people. Maybe at Star Labs. Maybe with your friends."

Caitlin squeezed her eyes shut. Her lips were just the faintest bit blue.

"They need me," she said in a tiny voice. "Barry needs - he gets hurt so often - and Cisco is so reckless sometimes - they need - "

"They need a keeper. I get it. Boys." Louise rolled her eyes. "It's a pickle. If only you knew someone else who could look after them while you take care of yourself."

She thought maybe that had been too obvious, but Caitlin's eyes widened. "Louise! You're a doctor."

"Does my medical license count, here?" Actually, it didn't even count on her own world - medical boards could be so picky about things like sold prescription pads - but Louise saw no reason to tell Caitlin that.

Caitlin waved a hand. The faintest curl of mist followed it. "I've never practiced except on Barry. And I have extensive notes. And you took care of me just fine."

She had, when she'd found Caitlin shivering with hypothermia on a ninety-degree day. She'd known the signs. She'd known right away why she was drawn to that particular street, that particular alley, a week after landing in a strange new world. She'd taken Caitlin back to her apartment and warmed her up with all the methods that had always worked on her own cold flares.

"Well, yes," Louise said slowly. "But how are you going to explain me?"

"You're a friend."

"And why are you sending in a friend, who looks almost identical to you?"

"I don't think we look that much alike."

"Enough so I can walk in your workplace anytime I like."

"Louise!"

"Relax, it was the one time we were going out to lunch." That Caitlin knew about. "Anyway, my point is, how are you going to explain sending in a friend, who looks almost identical to you, while you traipse off to the Arctic? Are you honestly going to tell them about the cold?"

"Oh, god, no." Caitlin went pale. "I can't. Not until I know I can control it."

Louise scraped at the sides of the ice cream container. "Well, if you just say, 'Here's my pal Louise, byeeee,' they're going to be a little suspicious. I don't think this'll work."

"You know … it would be a lot simpler if you just posed as me."

Yahtzee. "Hmm. Really? We're going to go the full Parent Trap?"

"You just said you could walk into Mercury anytime you wanted."

"Mercury's different than Star. More people, for one."

Cailtin hopped up, shedding the blanket. "Come on. Let's try this."

"What?" Louise allowed herself to be pulled up. "What are we doing?"

"Fashion show. Come on."

Louise trailed along after Caitlin to her bedroom, which sported floor to ceiling mirrors on the closet doors because that woman was a clotheshorse, honestly.

"Come here," Caitlin said, steering her in front of one. "Here. Let's just look, okay?"

They leaned against each other, peering in the mirror.

Setting aside Louise's heavier makeup, and her tight, torn jeans and low-cut shirt, the similarity was pretty clear. They were the same height, the same build. Louise's hair was a little darker, her skin a little more pale.

The ways of the multiverse continued to surprise Louise. In this world, the Flash was a scrawny, nerdy kid. In the pictures on Caitlin's phone, he was about as imposing as a scarecrow. He looked more heroic in his suit, but as far as Louise was concerned, Jay Garrick was still the preferred Flash.

You know.

If she had to pick.

Anyway, Jay Garrick and Barry Allen were just about polar opposites, where she and Caitlin Snow could have passed for twins.

"We are very similar," Caitlin said.

"Mmm." Louise put her arm around Caitlin's shoulders. "I think I'm cuter."

"This is not a contest of relative cuteness," Caitlin snipped, which Louise took to mean she agreed.

Caitlin brushed fussily at Louise's bangs. "I've never worn my bangs that way."

"Women change their hair all the time." Louise reached out and combed some of Caitlin's hair over her forehead, so it fell more or less in the same way that Louise's bangs did. "What do you think?"

Caitlin twisted her mouth, staring at herself. "The real test is how my clothes look."

"Oh, ugh, snooze."

"Shut up. I like my style." She opened up a closet door.

Louise went right for a really cute, short, beaded number. "Oh, this now - "

"Is not proper work attire!"

"Should have known. It looked too fun. Have you ever worn that?"

"Only once, and it ended badly."

"How badly?" Louise said with interest.

"Karaoke and a hangover."

"Even your poor choices are boring."

"You've never heard me sing. It was an extremely poor choice."

Ooo. Note. Louise liked her own singing voice - she was no opera star but she didn't scare small children, either. Apparently Caitlin did.

Louise picked out the most boring dress she could find, and was rewarded by a nod of approval. "That'll do."

Louise pulled off her shirt, and Caitlin spun around. "God. Would you warn me?"

"It's nothing you haven't seen before!"

"Only because you never warn me."

"You're safe, I'm decent," Louise said a few minutes later. Depressingly decent. She couldn't remember the last time she'd worn a skirt that covered her knees.

Caitlin looked over her shoulder, then nodded. She pointed. "Shoes."

She held up a pair of spike heels. "Really? Do I have to?"

"Yes," Caitlin said, putting her hands on her hips. "I wear them all the time. It'll be noticeable if you suddenly switch to flats."

"Why do you do this to yourself?" Louise asked, stepping into the heels to teeter in a small circle around Caitlin's bedroom. Ugh. Give her motorcycle boots any day.

"I like them. They make me feel powerful."

"Lambchop, you get control of the cold and you'll be able to freeze a man's heart in his chest from twenty paces. How's that for powerful?"

"I don't want that."

"Too bad, you've got it." And Louise didn't, anymore.

Caitlin pulled Louise's hair out of its ponytail and styled it. Louise had to admit she looked pretty good. And an awful lot like Caitlin.

They studied each other in the mirror again.

"I think we could do this," Caitlin said. "But you'll have to be very careful. You need a full background on me. On everybody." She worried her bottom lip.

"I don't know. I think Barry might figure it out."

"Barry's rather unobservant. It's Iris you'll have to worry about. And Cisco. If you can fool them, you'll be fine."

"Well, that's your job. Give me full dossiers so I can do mine."

"One more thing," Caitlin said. "Stay away from Cisco."

Louise poked through Caitlin's jewelry. There was a distinct lack of bling. "I thought I was supposed to be fooling him. Don't you think that'll set off alarm bells?"

"You can be friendly. It's better if you are because otherwise he might get suspicious. But no good-natured sex between friends, do you hear me? When I get this figured out, I'm coming back, and that's a complication I simply don't want."

"You just don't want to miss the fun," Louise said, but she held up her hand. "Okay, fine, I will leave your precious cupcake of a man alone." Too bad. She really did have the feeling that Cisco Ramon knew how to make a woman come back for seconds. But she was going to be busy enough that she probably shouldn't let herself get distracted.

Probably she should feel guilty, she thought later, walking back to her apartment one block over with her bag full of flash drives containing Barry's medical information to read through. But this was survival, and Louise Lincoln, once Killer Frost, was practical above all. If other metas from her world were turning up here, than Zoom and Jay Garrick were probably not far behind.

And in that case, Star Labs was the ideal place to watch out for them.

FINIS