The Flash Recap With Spoilers: King Shark

The episode opens where last week's left off, with Caitlin in denial that Jay is dead, standing in front of the Speed Cannon while the rest of the team stands by in disbelief. Barry asks Wells to open the breach to Earth-2 so he can go back, but Wells says there's no way to reopen them.

Jesse is upset that they can't go home, and the rest of the team is upset that there's nothing they can do — but Barry stalks off, determined.

Elsewhere, Cisco is examining his Vibe shades while Caitlin sleeps; she refuses to go home. Barry and Cisco are worried about her, but Wells says she's strong and will be fine. He tells them not to tell Caitlin, Joe and Iris about their lives on Earth-2, since it's better not to influence their lives in ways they shouldn't be.

Flash forward a while, as Barry explains to the audience that they tried their best to forget about Earth-2 and adjust to the new circumstances. Caitlin, though, is still working on the Velocity serum and keeps Jay's helmet on her desk.

At an Aquarium, a team of guards are trying to feed King Shark. When it doesn't come to get the food, they turn off the electronic security to look for him.

Elsewhere, Diggle and Lyla are flirting, talking about Lyla's new role as the head of A.R.G.U.S., when an alarm goes off. They run to the aquarium to see King Shark chowing down on a guard. He runs off rather than confront them.

At home, Barry is playing family games with the Wests. Wally leaves to go see some friends, and the other two ask Barry what's going on. Barry tries to wave it off, saying Wally doesn't like him too much, but the Wests just tell Barry he has to get to know him. Barry excuses himself to go to bed, and Joe and Iris wonder what happened on Earth-2.

At S.T.A.R., Caitlin is back in antisocial mode when Cisco tries to encourage her. Cisco tells Barry after she leaves that he's worried about her becoming Killer Frost, but before they can finish the conversation, Diggle and Lyla show up to warn him King Shark is coming to kill The Flash.

Barry decides he's going to go after King Shark before King Shark comes to them, and that he's going to do it himself rather than waiting for A.R.G.U.S. He's going to go to the waterfront, while A.R.G.U.S. takes the rest of the city.

Diggle says his helmet could use some work, and Cisco says he'll get on it. Meanwhile, Joe calls and tells Barry he has to come help Wally with a project tonight.

At Nautilus Labs, Cisco and Caitlin meet up with the widow of King Shark's Earth-1 doppelgänger, who was killed by the particle accelerator explosion. They ask her for her findings on sharks. Caitlin is short and rude, and eventually asks Cisco why he's been different to her since Earth-2.

At the waterfront, Diggle tries to talk Barry out of carrying the weight of the world on his shoulders like Oliver does. Eventually, King Shark arrives and kills a couple of A.R.G.U.S. agents.

Later, Diggle and Lyla lament the fact that King Shark got away and nobody can seem to find him. Barry has to excuse himself to go spend time with Wally.

Barry takes a look at Wally's application for an engineering program — it's for turbine-powered cars. Barry starts offering him some fairly harsh constructive criticism, but Wally quickly gets offended. When everyone starts giving Barry looks, he offers to start over and go over it together with Wally.

At S.T.A.R., Caitlin isn't impressed by the shark research from Nautilus. When Cisco offers to help her, she gets upset. Ultimately in the course of their conversation, Cisco tells her about Killer Frost. She tells him that she's only being cold and distant because she has to as a coping mechanism right now. She says she wants to focus on work and how to find King Shark.

Elsewhere, Wells is working on the white board when Jesse comes in and helps him figure out some variables in his search for King Shark.

At the West's, Wally and Barry are working on the project together. Wally gets annoyed that Barry seems to be trying to do it for him. He's upset that the Wests think Barry's perfect, and bails on working together. Just then, King Shark pounds through the wall of the house looking for The Flash.

Joe sends the family away and takes a few shots at King Shark with his gun to distract from Barry sneaking outside to change.

Barry tells King Shark that there's no way for him to get back to Earth-2, that the breaches are closed, but before he can do anything to take King Shark into custody, he's tossed aside. King Shark tells him that even The Flash can't catch him in water and makes his escape.

Back at home, Wally is confused as to why the family took all of that crazy in stride. He also attacks Barry when he comes back downstairs, calling him a coward for hiding out. When Wally storms out and Joe demands answers, Barry tells them about what happened on Earth-2. He tells them that it was impossible not to get emotionally sucked in because even though it's not his world, it's still real and he's responsible for Joe's death on Earth-2. He feels terrible that he left Earth-2 at Zoom's mercy when the breaches were closed.

Back at S.T.A.R., they speculate that King Shark cn sense the electricity in Barry's system, and that they can essentially use that ability to track him back.

That night, they set up an electric beacon to mimic the Flash's bioelectric field and lure the shark in. It's not working right away. While they're waiting for him to show up, Barry says that he's been running away from things instead of toward them lately, and that needs to change.

Cisco gets a reading on King Shark attacking the Flash-shaped bait on their beacon, which A.R.G.U.S. uses to try and lure him in. When it doesn't work, Flash sends Caitlin away so he and A.R.G.U.S. can fight King Shark on their own. King Shark tells him that he's going to kill The Flash, and then he'll kill the A.R.G.U.S. agents, but The Flash lures him away by running across the water and then, when King Shark is out at sea, electrifying the water by running around King Shark in circles. Trapped in a vortex of lightning, King Shark finally passes out when Barry throws a ball of lightning directly at him, and then runs back to shore.

On the docks, Lyla says she plans to try and cure King Shark rather than weaponizing him in the Suicide Squad. Caitlin suggests she give Nautilus a call. After the ladies leave, Diggle gives The Flash a pep talk about dealing with his grief over lost brothers in arms.

Later, at Jitters, Wally lets Joe look at his proposal for the turbine car. Joe's hugely impressed, but Wally admits Barry gave him a lot of help. Joe tells him that it's still his idea, and Barry would say the same thing. He tells a frustrated Wally that he's always been overprotective of Barry to help him get through the tragedy of his mother's murder, and that the reason they're so proud of him is that it could have gone differently. He tells him not to compare himself to Barry, that they're both his sons.

At S.T.A.R., Caitlin puts her cold hands on Cisco, taunting him with the specter of Killer Frost. She asks him to stop worrying about her, and that Killer Frost will never exist on this Earth.

They all go to the cortex to see Barry, who apologizes to them for the consequences of his choice to travel in time last year. He tells them that he knows Zoom and Jay's death are because of him — but that he is determined that Team Flash will also be the ones to stop Zoom. He says the breaches aren't closed forever, and they aren't done with Earth-2. He unveils a trophy case where Jay's helmet is mounted, saying that his sacrifice won't have been in vain, and that the next time he meets Zoom, he'll be a tim.

On Earth-2, Zoom takes Jay's body and drops it on the ground before the man in the helmet, who is visibly shaken. Zoom removes his mask to reveal Jay's face, calling it a complication.