Barry runs up and grabs Wells but is immediately shot back by the same device that just brought down the shark.

"Barry!" Caitlin yells, running up trying to get the brace that is electrocuting him off his leg. She turns to Wells. "Turn it off!" She demands.

He walks up and kneels down next to Barry, pressing a button that stops the flow of electricity. Barry lays back, relieved that the pain stopped. He looks up at Caitlin who seems tense, but not surprised. She looks at Wells out of the corner of her eye, keeping her head turned toward Barry.

"Who are you? What do you want?" She says in a menacing whisper.

He stands up, keeping his gun aimed at them. "I'm Dr. Harrison Wells. I'm here to help you stop Zoom." He says firmly.

Barry looks from Caitlin to Wells and back to Caitlin. She closes her eyes and takes a deep breath. He reaches up and grabs her wrist gently, rubbing her hand with his thumb. He looks back to Wells.

"How do you know about Zoom?" He asks, eyeing the gun.

"He was terrorizing my earth long before he decided to invade yours."

"Your earth? Earth 2?" Barry asks.

"If that's what you want to call it." He says, sounding almost offended by the informal name.

"You're his doppelganger." Caitlin says to herself, but Barry and Wells both hear her.

"I am me." He says gruffly. He disarms the gun and moves it away from their face, leaning down and offering his hand to Barry. He stands up and helps Caitlin to her feet. "Now, if you're ready to get started, I'd like to better inform you and your team what you're up against. Your strategy so far has been disappointing and inadequate at best."

"My team?" Barry asks, wondering how this man knows anything about them.

"Yes, your team. This young woman, the cop, and the short one." He says, shifting the gun to rest on his back.

Barry turns to Caitlin. "We need to take care of this." He motions to the shark." Caitlin nods.

The next thing Caitlin knows, she is standing in Barry's lab with the gun that was around Wells' back. Wells is handcuffed to a chair in front of her. Barry is nowhere to be seen.

"This is unnecessary." Wells sighs angrily.

"Not to us." She says flatly, not looking at him.

Barry runs back in with Joe. Joe's eyes widen and he immediately pulls his gun from its holster and aims it at Wells, being only a motion away from pulling the trigger, Barry yells at him. "No! Joe, it's not him." Barry grabs the gun away from Joe, not missing Caitlin stepping closer to Wells out of the corner of his eye.

"What's he doing here?" Joe yells.

"It's not him." Barry says in a calmer voice now. "He's just a doppelganger." Wells rolls his eyes at the condescending title. "We have bigger problems."

"Bigger than this?" Joe asks, pointing to Wells.

"Yes." Barry says.

He walks Joe to the window of his lab and points outside. Joe looks out and looks back at Barry confused. "Look down." Barry instructs. Joe looks down and sees a large shark with arms and legs tied up in a net, hanging from the window.

"Damn. That is a big problem." Joe says.

"Any ideas on what to do with him?" Barry asks.

"Kill it." Wells says flatly.

Barry and Joe turn to him. "Didn't ask you." Joe says.

"I may have an idea." Caitlin speaks up. All of them look at her expectantly. "Diggle's wife, Lyla, she's in charge of A.R.G.U.S. now."

"The research facility in Star City?" Barry asks.

"Government run. Carries out a lot of secret defense and anti-terrorist ops. Research facility on steroids, and with a fragile agenda. but yeah. That one." She confirms. "She's been trying to make them a little more...straight arrow, no pun intended. She might be willing to help. And they'd definitely have the resources."

Barry nods. "Do you know her enough to ask her?"

"I know her enough to try."

Caitlin calls Lyla and, after some slightly manipulative begging and negotiating, Lyla agrees to take in the shark, claiming they'll find some way to learn from him without weaponizing him.

"Thank you, Lyla." Caitlin says before hanging up the phone. She looks to Barry. "Can you get him to the roof?" Barry reappears just seconds later, nodding with a smile on his face. "I'll take that as a yes."

"Well done. Now can we get back to S.T.A.R. Labs?" Wells says unenthusiastically.

"How do you know about S.T.A.R. Labs?" Barry asks.

"That's where he came over." Caitlin says nonchalantly while looking at the shark teeth on Barry's desk.

"How did you know that?" Barry asks. Caitlin panics and looks at Joe. "What aren't you guys telling me?"

"I saw him in S.T.A.R. Labs the night you got the stabilizer running. I'm assuming that's when he came over." Caitlin admits.

Barry looks at Wells who nods, then looks back at Caitlin. "Why would you not tell me?" He asks, anger clear in his voice.

Caitlin grabs his arm and pulls him away from Wells. "Look, I was going to, but that was the day we fought about Wells and Jay, and I honestly thought I was seeing things. It scared me."

"That's why you went M.I.A. the next few days." He says. She nods. "What changed your mind?"

"Joe said Dr. McGee thought she saw Wells leaving her lab the night Mercury Labs was robbed."

Barry quickly turns to Joe who shrugs and mouths 'sorry'. He runs his hands through his hair and sighs. "Anything else you're keeping from me?" He asks Caitlin and Joe. They both shake their heads.

They all turn when Wells clears his throat. "I don't mean to interrupt, but...Zoom?" He reminds them.

"Why do you want to help us?" Joe asks, skeptical of Wells and his intentions.

"As I told Mr. Allen here, Zoom has been terrorizing my earth too. We've been unable to stop him, but I believe with my help, you will be able to." He says arrogantly.

Joe leans over to Caitlin. "I know I tend to ask this a lot, but uh, any tests you can run here to prove this?"

She nods. "When we get back, yeah."

Barry runs them all back to S.T.A.R. Labs. Cisco sits there with wide eyes at the sight before him.

"That's not Big Belly Burger." He says.

"Oh, shit!" Caitlin says. "I left the food in front of the building."

"No food?" Cisco whines, momentarily forgetting about a copy of his dead, murderous boss being in the room. Caitlin shakes her head. He frowns and then turns to look at Wells. "Hi?" He says, narrowing his eyes.

"Hi." Wells says back dryly.

Barry and Caitlin explain the evening's events to Cisco who sighs and slumps in his chair. "I thought doppelgangers would be cool. Alternate universes are supposed to be cool. Not this." He says, motioning toward Wells who glares back at him. Cisco takes a deep breath and straightens up. "So, let me get this straight. This guy is the doppelganger of the man who murdered Barry's mother, kidnapped Eddie, got Ronnie killed," Cisco starts but Caitlin cuts him off.

"He's the doppelganger of a man who was killed fifteen years ago. That's it." Caitlin says, almost convincing herself.

Cisco glares at him.

"He saved my life." Barry cuts in, trying to convince Cisco to give him a chance. Cisco turns to him with a look of surprise.

"Giant shark almost ate Barry." Caitlin explains.

"What?" Cisco shouts, sounding disappointed. "How giant?"

"The biggest I've ever seen." Barry answers.

"Ah. The king of the sharks. The shark king." Cisco sighs to himself. "King Shark!" He shouts.

"Caitlin, you said you could run some tests to prove if this...Wells is telling the truth?" Joe speaks up, rolling his eyes at Cisco.

"None of your tests will reveal anything. My DNA will be indistinguishable from the Harrison Wells from this earth." Wells argues.

Caitlin walks closer to him, motioning for him to go to her lab and the med bed. She doesn't look up at him as she walks by him. "That's what I'm counting on."

Barry, Joe, and Cisco stand in the cortex watching Caitlin and Wells like hawks.

"You can tell your guard dogs to stand down." Wells says.

"Wouldn't dream of it. They'd never agree anyway." She says in a flat tone matching his.

"I am no threat to any of you. Zoom, however," he starts.

"Yeah, we've been given the spiel. Unstoppable demon. Face of death. Yada yada." She says.

He reaches and grabs her arm harshly. Barry takes a step forward in the other room, but Joe reaches and stops him.

"I would not take him lightly, Dr. Snow. He will destroy everything you love." Wells says in a hushed, angry voice.

Caitlin pulls her hand from Wells' grasp. "We are not unfamiliar with that threat, Dr. Wells." She says in a formal and poor attempt at a polite tone.

The two remain silent for a few minutes while Caitlin finishes with her tests.

"Are you about done? I'd like to catch Zoom this year if you don't mind." He snaps at her. "Ow!" He reaches for his arm where she just snapped the band that was squeezing his arm for blood more aggressively than usual.

"So sorry." She says insincerely. "Look, you want our help. Keep claiming you're here to help us all you want, but clearly you didn't have great luck on your earth. If you want our help, you need our trust. That doesn't come easy nowadays."

"Thus, the tests." He mumbles.

"Yes." She snaps back.

"What are you attempting to prove, Dr. Snow? What will these tests tell you about whether or not you can trust me?" He asks.

"Your doppelganger on this earth is dead. The only other man that looks like you...well let's just say confronting him again is something we'd all rather avoid. So, we're just ensuring you're telling us the truth about who you are. Honesty goes a long way with us."

"So, it's my face." Wells half-heartedly laughs. Caitlin nods. "Is that why you can't look at me?" He asks darkly. Caitlin doesn't answer. Wells walks up to her desk where she is standing. He stands on the opposite side. "Everyone else, they look like they want to shoot me, but you...you can't even look at me." He's smirking. He slaps his hand on the desk. "What did he do to you?" He asks, sounding almost amused.

She swallows, her hands shaking. She's angry. She looks up at him meeting his eyes, a look of determination on her face. "Nothing." She says harshly. She sets down her tablet and walks out of the room. "I'm done. You can go." She says dryly, walking out of her lab and straight out of the cortex.

"Cait." Barry steps to go after her but stops to turn back to Wells who is walking in with a smug look on his face.

"Do you have a Big Belly Burger?" Wells asks.

"Unbelievable." Cisco scoffs.

"I believe I passed the first round of tests. I'd like food before you subject me to the next round. Or we could skip all that and start working to stop Zoom."

"What the hell is he doing here?" Jay shouts, storming into the cortex.

"I should've known Jay Garrick would be hiding out on another earth." Wells scoffs. "Everyone thinks their beloved hero is dead."

"I almost was. I fought Zoom and lost my speed, and almost my life."

"You're a coward Garrick. And pathetic. You 'fought' no one. You only challenged Zoom enough to make him stronger. Leave it to you to travel to another earth to find another speedster to do your work for you." Wells spits at him.

"And what are you doing?" Jay accuses.

"Your job for you."

Jay jumps at Wells, but Barry jumps in front and stops him. "Chill!" He glares at both of them, lingering longer on Wells. "We have bigger problems. Look it's been a long day. Everyone just needs to get some rest and we'll...revisit all this tomorrow."

"You're wasting time." Wells argues.

"Maybe. But Zoom hasn't shown his face here yet and until he does, we don't know what we're up against." Barry says.

"I can tell you. He-" Wells is cut off.

"Is sending other people to do his work. For now, we just need to deal with them." Barry says. "Now, you all can do what you want, but I'm calling it a night."

Wells rolls his eyes and Jay huffs before walking out of the cortex. Joe and Cisco walk out with Barry. Barry tells them goodnight before they get on the elevator, as he leaves to go find Caitlin.

"Barry!" Cisco calls, stopping the elevator doors. "Try Wells' office." Barry nods and walks to Wells' office instead of the roof where he had planned on checking.

"Knock knock." He says softly as he walks in, seeing Caitlin spinning slowly in Wells' office chair. She stops turning and gives him a weak but genuine smile. "You okay?"

She nods. "I just needed to get away from him for a minute."

"I understand." He says sitting across the desk from her. "Mind if I ask what made you come up here?"

She gives him a knowing smile. "You can ask me anything. I don't really know why I came here. I just...I guess needed to remind myself that this Wells is gone. Try to separate the two. I mean, just talking to that Wells down there, he's nothing like...this earth's Wells...or Thawne, or whatever. I'll get over it. Just need time. He just pissed me off." She laughs lightly.

He smiles at her. "Well, he seems to get under everyone's skin. Apparently, Jay and him know each other. Not the best of friends."

"Surprise surprise." Caitlin laughs.

They're quiet for a moment.

"You said I could ask you anything?"

She looks curiously at him. "Of course."

"Why'd you walk out of my lab earlier? You said you were going to dinner with Iris, but you weren't." He asks sadly.

"I uh-"

"Cuz there's nothing going on with me and Patty. She just wanted to write some reports together and look at the shark teeth and Iris said you might've thought that there was something going on because we haven't really figured out what we are yet and I don't want you to get the wrong idea and it seems like you might have and then I know you saw us walking later too before the whole shark incident and I lo-"

"Barry!" Caitlin laughs, reaching across to grab his hand. "Breathe." She smiles softly at him, walking around the desk and sitting next to him. "I didn't think anything was going on between you and Patty."

"You didn't?"

"No. She's been pretty quick to figure things out where the Flash is involved. I was scared if I mentioned Cisco it'd start connecting too many dots for her. Kinda panicked." She explains.

"Oh." He says, blushing a little. "I thought, maybe you got a little-"

"Jealous?" She asks, raising an eyebrow. "Should I be?"

"No. Absolutely not." He quickly says. He scoots closer to her, grabbing her hands in his. "A wise person today told me to make what you and I are a little more clear. At least what I think we are."

"Iris?" Caitlin asks, smiling.

Barry nods. "We're doing this a little out of order, but uh, you already know that I love you." Caitlin nods. "And you already know that I am here for you, no matter what." She nods again, smiling at him. "But I want you to know that I don't want to be with anyone else. I just want to be with you, as much and as long as you will let me."

Caitlin leans forward with a smirk. Her nose is just an inch from his. "Barry Allen, are you asking me to be your girlfriend?"

He laughs lightly and looks down. "Yes?" He says, not really knowing how to word it since 'girlfriend' doesn't quite cover how he feels about her.

Caitlin moves his chin up. "Look at me." She whispers. "Yes."

Barry smiles and pulls her in for a kiss. She steps forward, sitting on his lap in the chair, deepening the kiss. He wraps his arms around her waist, and she threads her fingers through his hair. He smiles and pulls back, leaving a final peck on her lips.

"So, you weren't worried about Patty at all?" He asks, mock-offended.

"Nope." She says, smiling. "She's way too much like you. If anything, you should've been worried about me falling for her." Barry's raises an eyebrow, leaning back. "Kidding babe. Kidding. I've only got eyes for you." She says softly with a smirk.

Barry smiles then yawns. "We've got a long day tomorrow."

"Then we should get to bed." Caitlin whispers to him, leaning closer again. Barry takes a deep breath before laying Caitlin down on the bed in her bedroom where they are now standing.

"Y'know, disorienting me is a weird method of getting me to bed." She says, shaking her head from the dizziness from being ran to her house.

"Worked, didn't it?" He says, smirking at her.

She sits up and scoots to the edge of the bed, giving him a soft smile. He walks forward and puts his hand on the side of her head as he guides her to lay down on the bed. She pulls him down with her, both of them staring into each other's eyes. Barry leans down and kisses just next to her mouth. She smiles and closes her eyes as he kisses her jaw, then her neck, undoing the buttons on her shirt. She runs her hands up his shirt, feeling the warmth of his skin.

"I thought you were tired." She shakily whispers to him.

He hums into her neck. "I can be quick." He whispers, referencing his super speed, but they both immediately take it a different way. Caitlin busts out laughing, and Barry buries his head in bed next to her neck. "I didn't mean it like that." He whines, laughing into the sheets.

He pulls back and smiles at her, admiring how she laughs. She finally stops enough to look at him and smiles. He leans down and kisses her quickly before standing from the bed. He takes off his shirt and puts on a pair of shorts, while Caitlin gets back in bed with nothing but a large t-shirt. Caitlin sets their alarm and Barry turns off the lamp. He pulls Caitlin over into his side and kisses the top of her head.

"I love you." He whispers.

She hums into his side, kissing his chest lightly. "I love you."