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Worlds' Finest Expanded

Prologue: Trapped

Somewhere Outside National City, Earth-38:

"You really think this is gonna work?" Kara Danvers also known as Supergirl asked as she stood beside him. That man, Barry Allen, also known as the Flash was from another universe and need Kara's help to get home.

"Well, watching Livewire and Banshee work together reminded me of something that we tried on my Earth once. You and I join forces. Literally. We combine your speed with my speed. If you throw me forward at your fastest, then I might just break the dimensional barrier and get back home." Barry said.

"What? What do you mean? Like a race?" Kara asked.

"Yeah, I guess. Think you can keep up, Girl of Steel? " Barry chuckled and Kara responded with a laugh of her own.

"Just you watch, Scarlet Speedster. All right. I'm gonna miss you, Barry Allen."

"I'm really gonna miss you too, Kara Danvers. Or Kara Zor-El. Which is your alien name. Because you're an alien which I think is very cool. I think James Olsen thinks so, too. "

"What makes you say that?" Supergirl asked, taken off guard by that sudden statement.

"You remember before when I told you to take things slow? That's good advice for a superhero, lousy advice for two people who really like each other. Maybe it's time to speed things up."

"Maybe," Kara said with a wistful smile. "Come here. " The two superheroes shared a quick hug.

"All right. Let's do this. On your marks..."

"Get set."

"Go!" The two superheroes took off quickly reaching their top speeds. The pair smiled at each other as Barry felt Kara grab him and throw him forward with all her immense strength and speed. However instead of the intended result of opening up at a dimensional breach that would take him back to Earth-1 the Flash found himself tumbling end over end and hitting the ground hard.

Barry found himself staring at the desert landscape in a complete stupor. He barely noticed Supergirl zipping up to him.

"Barry are you okay?" She asked.

"It didn't work. I'm stuck here." Barry said numbly. "I'll never see home again. I'll never see Iris or Joe or any of them again."

"We can try again Barry. You got here, there has to be a way for you to get back."

"It's no good Kara, that was my only chance, I'm stuck here."

"What if we had Winn make me one of those tachyon devices? We could use that to jump my speed up and maybe that would be enough to help you breach the dimensional barrier."

"It wouldn't work. The tachyon device is meant to supercharge the Speed Force in my cells, that's how it makes me go faster. You have super speed, but you aren't connected to the Speed Force. The tachyons wouldn't boost you like they do me."

"Barry I'm so sorry. I promise that we'll find a way to get you home."

"It's not your fault Kara."

"Listen why don't you stay at my place for now, at least until we can sort something out. I'm sure the D.E.O. could make some credentials for you so you can do so work and live a life while you're here." Kara suggested.

"Thanks Kara, I guess I'll have to take you up on that. Right now though I just need to run and clear my head.

Earth-1, Central City, S.T.A.R. Labs:

Cisco Ramon stared blankly at the monitors trying to comprehend what he was seeing. It had been ten minutes and there was no sign of Barry anywhere, the tachyon device had made him faster than ever so there was no reason it should have taken Barry this long to get back to the lab. "He's gone. I don't know how but he's just gone."

"Maybe he ran farther than he intended, have you tried expanding the satellite's search range?" Dr. Caitlin Snow asked.

"That was the first thing I tried Caitlin, it's still looking for him, if he's still running then he's really overshot the goal. Like crossed the state line overshot." Cisco said.

"Do you think maybe he traveled back in time again?" Caitlin mused.

"That's incredibly unlikely, chances are if Mr. Allen made an unintended time trip we wouldn't be here right now. His efforts to get home would drastically alter the timeline to the point that the situation that got us here would have never happened." Harrison Wells from Earth-2 interjected.

"Thank you for that Harry, now do you have any idea what might have actually happened to Barry?"

"No, Ramon, I don't have an answer, I've never dealt with tachyon enhancement before. We did get those schematics from Thawne, who hates Mr. Allen with a burning passion, maybe he sabotaged Mr. Allen in an effort to destroy him."

"No, Thawne only had a few hours at most, even he couldn't mock up something convincing enough to trick us and also kill Barry in that amount of time. Besides Thawne really hated Barry, he'd want to take him out personally." Cisco countered.

"Dr. Wells has a point though, what if the tachyon device overcharged Barry's cells like Velocity-9 did to Eliza Harmon? He could have just faded into nothingness." Caitlin said. Cisco shook his head.

"No, I triple checked the math. There's no way the tachyon device should have done to Barry what V-9 did to Trajectory."

"Well if he didn't go back in time and he didn't disintegrate like Eliza then..." Caitlin began, Cisco picked up on her train of thought immediately.

"The only other option is that he went through a breach. Barry's on another Earth. He must have run so fast that he punched through the dimensional barrier. Man that's cool."

"Then why isn't he back yet? If he can run fast enough to make a breach why can't he run back?" Caitlin asked.

"It's possible that the tachyon device was damaged during the trip and there's no guarantee that Barry ended up on an Earth where there would be someone willing to fix it. We may have to find a way to open a breach to get him back."

"No, you're not opening any breaches. I won't let you." Harry said.

"So you're saying we should just leave Barry trapped on another Earth?" Caitlin asked.

"What I'm saying Snow, is after all the trouble we went through to close the breaches I'm not going to letting you open them again. Right now Zoom is trapped on Earth-2, which means that my daughter is out of his reach. That's all that matters to me." Harry replied.

"We don't want anything to happen to Jesse either, but we can't just leave him stuck on another Earth." Caitlin said.

"Mr. Allen isn't the be-all and end-all. We don't even know what Earth he is on. If we go around opening up breaches we're practically inviting Zoom back to this Earth or possibly something even worse than Zoom and without Mr. Allen what little chance we had to stop it would be gone. It's best for all involved if we just consider Mr. Allen lost to us."

"Fine then you can be the one that tells Joe and Iris that Barry isn't coming home, but we're not going to leave him stranded out there. We'll get him back no matter how long it takes." Cisco said coldly.

So this is just a prologue to show off the premise, future chapters will be longer. Next we'll continue with the Supergirl plot with Barry added of course and more fall out from Barry not being on Earth-1. Please review. I welcome all ideas and feedback.