A/N: This is a one-shot fic combining my Marvel fave, Spider-Man, and my DC fave, The Flash. It's not connected to the alternate-universe canon of my Spidey & Speedy fanfic trilogy, though. It's part of its own AU, separate from anything else I've written. Like all my other fics, though, it uses Andrew Garfield's and Grant Gustin's portrayals of their respective signature characters as the basis for the story in my mind. This AU crossover takes place on timelines concurrent, roughly, with early Season 4 of The Flash (the primary difference being that WestAllen is not a canon couple in this 'verse), as well as the period of The Amazing Spider-Man 2 where Peter's broken up with Gwen and is starting college (though he's going to school in Central City, not in New York.)

Many thanks, of course, to the great Whisperingwater for inspiring this fic with a stellar prompt based on an Instagram find in which Peter comes to Central City to be Barry's lab assistant. How could I resist?

Enjoy!

WALKING THE WIRE

It used to be that I could work the crime lab all by myself, but with the brass unaware of my powers and convinced that I couldn't possibly be efficient on my own, they insist that I have a partner. Even when there comes a week when Julian's finally taking a vacation and visiting his family back home in England. So those bright sparky dicks, not to sound too Winchester brother-y, decided it was high time I took up training duties for a brand-new intern not even a year into his studies at CCU.

While waiting for the intern to arrive, I take a look at the material he sent up in his application. Not to me personally - or Julian, for that matter, he being the senior CSI - but to HR, who forwarded said application my way. Name: Peter Parker. Salutatorian at Midtown Science High School in New York City - which explains why his contact number has an area code I don't recognize. Graduated last year - which explains why he's got virtually nothing under employment experience, save for a mention of freelance photography for this trashy tabloid called The Daily Bugle. But he's majoring in biotech, which certainly piqued my interest and made me want to pick him out of all the interns whose info HR sent me.

There's a knock on the door, and I call out, "Come in."

This must be Peter Parker. Average height, but he looks taller with his slender build. Dark green peacoat, pseudo-military style. Large square glasses over brown eyes. I'm thrown, though, by his large, prominent eyebrows and his extra-messy hair, both of which combine to make him look like he could be my little brother.

I pretend not to know who he is, though. "Who are you?"

"My name is Peter. Peter Parker." Also like me, he's got a surprisingly deep voice. "I'm your new lab assistant."

"Barry Allen." I stand up from my desk and come around to shake his hand. I almost hate to be so relatively terse with him, but then again I am his boss, at least for now. It's such a strange feeling. I just hope the power doesn't go to my head or something. "Interesting that HR would even give your application the time of day," I tell him. "Normally, they want someone who's at least a junior."

"I know..." Peter lays his messenger bag on the nearest chair. "I know, but I applied anyway on the off chance I could get in, so I guess they must've seen something in me." He looks up, smiling even with his eyes, if only for a moment. "And so did you, I bet."

"Yeah, maybe."

"Really?" God, this kid is adorable. So much me at eighteen, but somehow even brighter. I just hope it's not covering some kind of traumatic past the way any chipperness on my part tends to do.

"Yeah, you said you did photography on the side?" I nod at his messenger bag. "Hope you brought your camera, 'cause whenever we have to go out and investigate a crime scene, you're taking the pictures."

Peter coughs loudly, and he keeps on holding his clenched fist over his mouth like he's trying to hold in puke.

I'm quick (though slow by my standards, of course) to hold up my hands and tell him, "Not to worry. The bodies around here tend not to be too bloody, you know?"

"Not like what they deal with back home, huh?" Peter asks.

"Wherever 'home' is for you," I laugh.

"You couldn't figure that out for yourself?" He almost looks offended by the very thought that I haven't.

"Yeah, I'm just messing with you." I'm tempted to reach out and ruffle his hair, but if he's anything like me, he'd probably flinch away at first. Give him a day or two on this internship, though, and maybe he'll warm up to me. "Queens, right?"

"Hope my attitude didn't give it away."

"Ehh, I've seen worse." Actually, the giveaway is his tinge of a New York accent. It reminds me a bit of my old college roommate, Dick Grayson, though Grayson came from New Jersey.

I raise my eyebrows. "I hope not. Sincerely." He raises his eyebrows back - is he playing the mirror game with me? "You'd be surprised, Pete." When I see him twitch, I ask, "Uh, you don't like being called 'Pete?'"

"It's not that I don't like it, it's just..." He shrugs. "Kinda weirds me out when people nickname me, for some reason. If it's 'Pete' or even 'Petey' - I get that one a hell of a lot - but it still feels like it's supposed to come from my dad or something."

Oh man, did I just open up a can of daddy issues?

Then a smile breaks out all over his face. "I'm just playing. You can call me 'Pete,' you can call me 'amazing,' just don't call me late for dinner, ya get it?"

"What kind of dinner do you like?" I ask, out of curiosity.

Peter's smile expands as he laughs his ass off for a moment. "You're a little old for me, boss, and besides, I'm much more into the ladies."

"Oh no, it wasn't..." I can't even finish my sentence because I'm laughing just as much as he is. Really, I should've seen that coming before I opened my mouth - of course he'd interpret that as me asking him out on a date. "I promise I'm not normally this unprofessional, though to hear my partner tell it, that promise was a lie."

"My girlfriend could be the same way," Peter says. "Well, ex, technically." His face clouds over, and I swear I see him wipe a trace of a tear from his eye.

"I didn't mean that kind of partner." In that respect, me and Julian would be absolutely for no. Especially given the (admittedly mild) professional power imbalance between us. And besides, I've got a most wonderful partner in Cait. I can hardly think of anyone more suitable for me. Well, maybe Kara, but our love is purely platonic. Same goes for Mike Matthews and his masterful mozzarella skills. That man, when he learned to spin a pizza, he took to it like a fish to water. No wonder he and Kara are so in love.

"Whoops, my bad." Peter brightens up for a moment. "So, uh, you really want me to be your photographer, huh?" He digs into his bag, pulling out a camera. I'm not kidding - it's an honest-to-goodness old-fashioned film camera.

"Love the hipsterity," I say, "but you're gonna need to have some more advanced equipment in my lab, I'm sorry to say." And he's covered for that too, holding up a shiny new phone. Relatively speaking. It looks new, but it's an older model. I get it - my first smartphone, when I was in college, it was a first-gen iPhone when that was at least a couple of years out of date. I still keep it hidden in a drawer somewhere at home, along with all my other phones - it's my tech graveyard. One day, Cisco and I will find some use for it. Heck, I might even enlist Peter's help for that task, if he's available.

Speaking of phones, mine buzzes in the holster on my belt. I check it and see it's an official message from Joe. We've got a new case. Not too far from here, but also pretty close to home, because it's only a block away from everyone's favorite hangout, CC Jitters. I text him back to let him know I'm on my way - with my intern, which would hopefully be enough to let him know that I can't speed my way down there this time, unfortunately. But I can at least drive as fast as I can through Central City's crowded streets - always a good challenge. A challenge I take on today with Peter in tow, though I'm not too happy to see his face a tad bit ashen when he jumps out of the passenger seat of my car.

"I promise, man, after we're done here, I'll speed you over to Jitters." I nod in the direction of my favorite coffeehouse, the sign shining brightly on the next block. "I find their espresso's better than a shot of whiskey for calming your nerves." And for him, he'd only need a single shot, not quadruple like I get.

"Ironic," Peter says, adjusting his glasses.

"There's a reason why ADHD kids are supposed to have stimulants."

Peter cocks his head as he follows me out the door. "Are you trying to say I'm an ADHD kid? You assumed I was neurotypical, you b...!" His voice trails off. No surprise that he doesn't want to cuss in front of me.

"No offense," I ask, "but...are you not? Neurotypical, that is."

"I'm certainly not typical." He wraps his hand around his wrist and wrings it, like some kind of tic. "You'll, uh, find that out pretty quickly if things go sideways."

For both our sakes, I hope that doesn't happen. I hope he's not so inexperienced as to totally freeze up in the face of danger. Though, then again, he's from New York, so I'd be surprised if he didn't gravitate more towards fighting than flying.

Out on the street, an entire block is cordoned off, and the usual Jitters crowd gathers outside the place, getting snapshots on their phones. Yeah, yeah, we're not important like celebrities, but they sure seem to think we are, if only for a moment. I hand Peter a pair of rubber gloves - they look a bit big on him when he puts them on, mostly because his fingers are so slim - and put on my own before approaching Joe. "What've we got? Human, meta, vegetable, mineral, or animal?"

Joe wrinkles his nose as he peeks under a corpse's sheet. "Hard to say. Unless we've got an actual ice-powered meta yet, this might be Captain Cold back in town. Where's he been, anyway?"

"Away." I don't elaborate any further, because I know he's gone off on some time-travel mission to save the world of tomorrow, along with a few other friends and enemies of mine. Where exactly he's gone, though, I don't know. Nor am I aware whether or not he's been successful, but if he wasn't, I probably wouldn't be here right now, would I?

(I'm hearing crickets, so I'll just assume I'm right.)

Joe looks up as he sees Peter approaching. "This your new intern?"

"Peter Parker." He shakes Joe's hand. "Uh, so, do you guys want me to get pictures of the body, or what?"

Joe nods curtly. "Bet you've never seen anything like this before, have you?" He pulls the sheet off the corpse, revealing it to be covered in ice so thick it's still slowly melting in today's heat.

While Peter starts to snap some shots of his own on his phone, I confer with Joe off to one side. "So..." he begins, clearing his throat a couple of times. "I know we already got an icy meta, but she wouldn't do something like this, would she?"

I shake my head adamantly. "Cait's in a better place now, mentally. She's got her powers and emotions under control."

Joe purses his lips. He tries not to say it too often, but for months now, he's been more than a bit leery of my relationship with Caitlin. Mostly because he can't help but think it's a little abusive on her part. Last year, around the start of winter, she started developing Killer Frost powers like her god-awful Earth-2 counterpart. She hid it from everyone else for a while, then her powers really forced themselves out and warped her brain. How, I'm still not certain. Maybe the sheer stress of trying to hide who she really was because she was afraid we would all reject her for it? (Wrongly so, I might add.) But one of the first things she did after becoming Killer Frost for the first time was, she kissed me and almost froze me to death.

Thing is, I knew she was still herself in there, somewhere, deep down. And she recognized that I recognized that, which, I think, is why she started spending more time with me than anyone else, eventually to the point where we decided to make our relationship official.

(Sorry, Iris. I think you and I can both agree we weren't really made for each other anyway.)

"All the same," Joe says, "I was, well, tempted to call her and find out where she was."

"Let me save you the trouble..." I dial STAR Labs.

"Good morning, you've reached the Library of Congress. For the President's Book of Secrets, press one and wait till the Russians hack you the election-"

"Nice try, Cisco." I almost have to bite my hand to stop myself from laughing, a challenge which, from the sounds behind me, Peter is failing. Cisco's been hanging around Mike too long. Or maybe even Grayson - I bet he's learned how to use his Vibe powers for intra-universal travel, as opposed to inter, by now, and probably Vibes over to Gotham once in a while to hang out with him. "Can you put Cait on?"

"Who's Cait?" Cisco deadpans. "I don't know her. I know a 'Caitlin,' though. Will she do?"

"Jesus, Cisco, you sound like you're setting him up with a high-class call girl!" Cait yells.

A smile breaks out over my face as I sigh with relief. Turning to Joe, I say, "See? She's fine."

As I say goodbye to my friends at STAR Labs - and promise to pick Cait up later for our double date with Mike and Kara down in National City - Peter, who's done taking his pictures, perks up and asks, "This Cait...I couldn't help but overhear and, uh, read between the lines...is she a meta?"

I debate answering for a second before telling him the truth. "Yeah, she's my girlfriend, and she's got pretty cool powers, and...wait a second." I look over his shoulder and see someone coming out from the crowd and ducking under the police tape at the end of the block. Peter turns around as well, almost in slow-mo to my speedster's eye, but still faster than I would expect for any non-meta. Even a young one.

"That's not her, is it?" Peter bends his knees a bit, lowering his center of gravity.

I narrow my eyes. The approaching person is female, visibly blue even at this distance. "But she was on the phone just now...this isn't my Cait. No, she must be-"

This Cait, clearly a Killer Frost from another Earth - not 2, I don't think; isn't she dead? - puts both hands in front of her chest and starts throwing her deadly ice beam.

I push Joe out of the way, and someone else does the same for me, someone who gets carried with me as I speed Joe to safety.

He and I both look at Peter in surprise as not only does he land on his feet mere milliseconds after we reach our destination, but he shoots what look like thick lines of spider silk out of the alley and back into the street. The silk lines land on the ice Killer Frost left on the ground in our wake, and Peter pulls on them, making the ice shatter loudly.

"I think we've got a few too many coincidences for one day," Joe says, trying to keep his cool despite being very shaken.

I reach out to Peter, who flinches away from me for a moment, even ducking and rolling like I'm about to attack him. Which I suppose I sort of am, given that I use my speed to force him to his feet and have him look me in the eye. "How'd you do that?" I look down at his hands, trying to spot the source of his spider webs.

Spider webs.

And he's from New York too.

God damn, but Joe's right. Too many coincidences.

"You're Spider-Man." It's not a question.

Peter brushes a stray lock of hair out of his eyes and pulls up one of his jacket cuffs, revealing the end of a bright red Spandex sleeve with raised black ridges. "Well, as long as the cat's out of the bag, you wanna kick some ass? Boss?"

"If we're gonna kick ass together," I say as Killer Frost approaches us, "you can call me Barry."

"But you can still call me 'Detective,'" Joe tells Peter as he draws his gun and raises it. "I'll cover you boys while you get into uniform. Go!"

Peter takes refuge behind a Dumpster. As I race past him, I get a brief glimpse of him shedding his street clothes, stripping down to the distinctive primary-hued Spider-Man suit, which he wears like full-body underwear. A little less armored-looking than my own suit - which I pick up in two seconds from STAR Labs - but very useful for allowing him considerable range of motion.

A range he shows off, along with some good snark. "Hey, lady," he says through the mask he's now put on, "even from here you're giving me chills! I'm gonna need a ton of chili to heat up again!"

"Better not," I laugh as I race around behind Killer Frost's back. Oh God, and she's got the exact same ass as Cait, and in a tighter outfit too! So distracting... "If he does, I hereby blame his belly bombs on you."

"You mean like from Big Belly Burger?" Killer Frost snickers and tries to hit me with another blast of ice, one that narrowly misses hitting my chest. As it is, the ice grazes my arm. "I don't think your friend can handle even half of one!"

"You should've seen me the night I first got these powers," Peter says. "I devoured my aunt's whole meatloaf! Nobody likes her meatloaf, but that night, it beat all other-" He jumps to avoid another ice shot - Killer Frost is going all out with both barrels as she lifts off the ground and away from us. "Oh come on! I was on a roll! Everyone loves this story!"

"I'm not here to be entertained, chums." Killer Frost rises higher, only for Peter to get his weblines onto her ankles and pull her down. The ice breaks again, and as she falls, I run up the side of the nearest building and jump out to catch her, even though she's liable to freeze me to death right then and there. But better that than her falling to her own death.

"That can also be arranged." Really, even knowing she's not my Cait, I'm sorely tempted to kiss her. Frigid she may literally be, but it doesn't make her any less beautiful. But for now, I content myself with something I haven't gotten the chance to do in a while - spiriting her to STAR Labs and locking her up in one of our specially-equipped metahuman containment units.

Cait - Earth-1 Cait, my Cait - is the first to come downstairs and see what's what, even beating Wally and Cisco. "Did you turn back time again?" she asks wryly as she watches her counterpart sit and fume in her cell. Not unlike when she was first struggling with her powers and we had to keep her locked for her safety.

"Dammit Barry!" Wally appears behind Cait, suited up, the sunny color of his uniform at odds with his crossed arms. "First you fight a meta without me, then you fight a meta with someone even cooler than me?"

"I what?" I look around and realize that I managed to bring Peter with me as well. He's still suited up, and surreptitiously disentangling the webs he hooked onto my shoulders before I left the crime scene downtown.

Cait and Wally both whistle at the sight of him, while Cisco walks in, cleaning his Vibe goggles with the hem of his Future Man shirt, and says, "Dude, are you sure you're on the right Earth?" He puts the goggles on - and now I think about it, since when do they need cleaning? "Okay, no, you're good."

I turn back to Peter, who's leaning casually against the wall. "Everyone," I say, "meet Spider-Man. Spider-Man, everyone. Kid Flash, Vibe, and the cooler, awe and somer Killer Frost...who's trying to freeze the hairs off the back of my neck as I speak."

"Those hairs don't yield easily," Cait says with a soft titter as her lips brush my skin.

"Yeah..." Peter ambles forward, his feet bouncing just a bit as he steps and his head bobbing to some imaginary jaunty tune. "Maybe Vibe's right. Maybe I'm a little more off the map than I thought. Here there be dragons, am I right...haha, just kidding! Well..." He rolls his neck and sighs contentedly, no doubt letting off a little more adrenaline steam. "I'm sure I'm technically still on the clock here, but...what's for lunch? Chili? Or maybe those Big Belly Burgers I've heard all about?"

Wally, the greatest Triple B connoisseur of us all, winks as he says, "They do have a Double Chili Patty on the secret menu. Shh! You didn't hear it from me!"

I draw Peter in for a side-hug. "Yeah, let's do lunch and talk about your place on this team, huh?"

"You mean...?" Even under his mask, I can tell he's got a banana-sized grin.

"You're not just interning for me anymore," I say, steering him out of the basement. At normal speed this time. "Welcome to Team Flash, buddy."