This is a "What if?" story that explores how Barry and Kara might have interacted had they existed in the same universe and become superheroes at around the same time. I strive to maintain the spirit of the characters established on the television shows as much as possible, but I do take some minor liberties with various storyline details compared to the canon of the shows. I like to think of it as yet another one of the Earths chugging along in the multiverse: largely the same except when it's not.

Some geographical notes: National City is assumed to be located near Los Angeles, CA. Starling City is assumed to be located near San Jose, CA. Central City is assumed to be located near Kansas City, MO.

The story will be a series of chapters loosely inspired by this video (which I did NOT make, just found on Youtube):

watch?v=GhYwwYRzOx0&index=7&list=LLiIG3wT07QAWasLwbmgz59w

The normal notes: Characters, environments, etc. belong to the CW. The continuity used is everything seen up to and including The Flash Season 2 and Supergirl Season 1. This is written purely for fun. Thanks for giving my story a chance.

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Author's note: All chapters in this story were updated on 12/31/2018. No major rewrites, just some clean-up of the writing. I hope you enjoy the story.

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"And with breaking news out of Metropolis, Superman has dazzled the city yet again with another…"

Kara had turned on the television while getting dressed. She didn't expect anything interesting to be on, as it was so early that the sky was still dark outside, but of course there was another story about another wondrous thing her cousin had done. Same old, same old.

Sometimes Kara was jealous of Clark and the way he openly used his powers to do good and help people. She could do all the same things he could, after all. Why shouldn't she be using her abilities the same way he was?

Then again, she'd been sent to Earth to watch over and protect Clark while he grew up, a job that was unnecessary from the moment she had finally landed. Did the world really need two superpeople? She knew how complicated her cousin's life was, constantly living in two worlds and having to hide one or the other from various people, especially those with less charitable feelings towards aliens. Blending in was simpler. Easier. Safer.

A sigh escaped her lips as her mind flipped through the same argument it had had with itself on and off since the day she was adopted. She hadn't come to a real conclusion yet, and she doubted today would be any different. Besides, she had to get going if she was going to catch Winn before he started his new job…in Central City.

Opening the window of her apartment, she looked upon the pretty National City skyline at night. In the dark clothes she was wearing, it was virtually impossible anyone would see her leaving. Coming back…well, she'd figure that part out later.

Looking back at the television, she saw an aerial shot of her cousin gliding among the skyscrapers of Metropolis, a dopey grin on his face after his latest good deeds. Kara rolled her eyes. "Always the boy scout," she muttered.

With that, she flipped off the television, tossed the remote onto a chair, and shot out into the night, flying at top speed towards Central City. Just because her powers were a secret from most people didn't mean she wasn't going to use them to see off a friend.

…

"Following his latest success in Metropolis, Superman calls for a unified team of heroes to address enhanced threats…"

Barry snorted. Yeah, Oliver would be thrilled with that idea. The idea of the Green Arrow working well with anyone, especially someone as squeaky clean as Superman, put a well-needed grin on Barry's face as he slogged through more paperwork.

Admittedly, Barry was a bit jealous of people like Superman and Green Arrow, who were making each of their cities, and the world in general, a safer place. Strictly speaking, he was too, working for the Central City Police Department as a crime scene investigator, but his efforts felt distinctly less impactful when they consisted primarily of filling in evidence descriptions and victim injuries. He frequently wished he could do more, but he had neither Oliver's unique training nor Superman's alien heritage. Ultimately, he figured he would have to make his peace with his contributions as a CSI, plus the occasional foray into Starling City to help Oliver catch some bad guys.

Lost in thought, Barry glanced at his watch and scrambled to his feet, realizing he was going to be late for coffee with Iris, and if he was late for that, he was probably going to be late in meeting up with the new guy he was supposed to show around the CCPD. His head swiveled between the door of his lab and the reports he had yet to complete, and he decided he would just have to take them with him and somehow finish them on the way. Hurriedly, he gathered the unfinished reports in his hands and stuffed a pen into his pocket before exiting his lab and locking the door. Glancing at his watch again, he saw he was now really late.

"Run, Barry," he sighed to himself. "Run." And he did.