People run through the streets of Central City. Flash and XS lie on the street paralyzed, with Grodd standing over them. King Shark arrives, and Grodd and Shark attack each other.
12 Hours Earlier
At STAR Labs, Cisco presents the meta-human cure to the others. The other wait for the eventual "but", but Cisco says that there are no "buts". Caitlin admits that they have to test the cure on a meta-human. They need a volunteer since they decided that using the cure was a choice, and they figure that no criminal at Iron Heights will give up their powers. Sherloque suggests that they use a meta from another world, and Barry remembers that there is already a meta from another Earth.
Barry, Nora, Cisco, and Caitlin go to ARGUS and meet with Lyla, and Barry introduces her to his daughter Nora. Lyla realizes that she's from the future, and they explain that they want to test the cure on Shay Lamden, aka King Shark. They want to talk to Shark and get his permission, and Lyla says that he's been talkative recently.
At the West House, Iris and Cecile look at photos of a young Wally and Joe assures them that Wally is at ease in Tibet and has no plans to come back to Central City. The couple's baby cries, and Cecile tells Joe that she'll deal with their baby. Once she leaves, Joe tells Iris that he knows about Cicada from Cecile. Iris says that the team will figure out a way to beat him. Joe suggests that Cicada is still getting help from someone, and Iris abruptly leaves to get more coffee.
Lyla takes the others to the docks and introduces them to Dr. Tanya Lamden, who is working with Shark, whose mind has been regressing. She's used a telepathic crown to stabilize the regression, and now she's helping her husband's counterpart to keep his human mind. Barry explains that they think they can make Shark human again and they came looking for a volunteer, and Tanya agrees to let them ask Shark. She uses the telepathic crown to explain to Shark what they want, and they agree that he should take the cure. Shark swims up to the dock and asks if the cure can help. There's telepathic feedback and Shark goes berserk, diving off into the water and swimming away.
Barry wonders what happened, and Tanya explains that nothing like it has ever happened before. She worries that Shay is lost forever, and Cisco suggests that she come to STAR Labs and they find a way to restore the telepathic crown. As the other leaves, Barry wonders if they should rethink how they're going to recapture Shark.
Iris and Joe have coffee and Iris asks if she can work there. Joe agrees and says that Cecile told him about her new office. She admits that her office isn't fully set up and Joe insists on sending her the phone number of his plumbers. Iris thanks him and quickly leaves.
At STAR Labs, Cisco and Tanya discuss how to boost the MAD Crown. Sherloque looks on, and talks to Tanya about her relationship with Shay. He's worked out that she's "familiar" with him and something more, and Tanya admits that they've grown very close but insures that he's just her patients. The two crowns link up and the MAD amplifies the crown's signal. Sherloque takes Tanya to get the earbuds for her crown. Caitlin calls saying that they've used their satellite to track Shark to the wharf.
Flash and Vibe breach to the wharf and Shark leaps out of the water. Nora arrives and puts the renovated crown on Shark, Tanya tries to get through to Shark and he grabs Vibe. Flash injects Shark with a drug and Shark falls back into the water after dropping Vibe. After a moment Shay climbs out of the water, reverting to his human form. Flash reports to Caitlin and Tanya that Shay is human again.
Back at STAR Labs, Caitlin examines Shay. He wakes up and panics, and Tanya assures him that it's okay. He realizes that he's human, and Barry explains that they injected him with the cure. Caitlin warns that there's still some dark matter in his pituitary gland but once they adjust the cure, it should be permanent. Sherloque asks Shay if it's the shark or the man that drives Shark, and Shay says that he should be held accountable for his actions. He remembers fragments of what he did as Shark, and felt rage. Shay says that today felt different, and he remembers the kindness that Tanya has shown him.
As Shay offers Tanya his hand, it transforms briefly. Caitlin warns that the dark matter in his body is replicating, and Barry tells Shay that they can't let him leave STAR Labs until it's over. Barry then tells Caitlin to tell him when the cure is ready. Caitlin and Cisco follow him out and points out that Barry gave Shark the cure without his permission. Barry insists that he did it to save Cisco, but Cisco says that being a hero isn't forcing people to take cures. He asks Barry if he changed his mind or that was always part of the plan, and walks off.
Iris is working at Jitters and Joe joins her. He says that he went by her office and she wasn't there, and she worries that Cicada could show up at any moment now that he knows who she is. Iris refuses to go back to the office, and Joe says that he's taking her to somewhere that he can show her how powerful she is.
That night, Caitlin tells Cisco that a mental signal overrode Shay's frontal lobe, resulting in a loss of judgment. The neutrotransmitters in the crown wouldn't have caused it. Barry comes in and apologizes, and Cisco punches him and then blasts him. Barry realizes that Cisco is being mentally control and superspeeds him into a pipeline cell. He returns to see Caitlin giving Grodd the telepathic crown. Grodd jumps out the window with the crown, and Caitlin ice-blasts Barry to cover Grodd's escape.
Once Barry recovers, Caitlin confirms that Cisco and Caitlin are back to normal. Grodd is concealing his location with his telepathic abilities, and Lyla explains that on the night of the Enlightenment, Thinker's dark matter wave took off the systems for one second. Grodd implanted mental instructions in a guard to drop the power dampeners. They figure that Grodd tried to control Shark but Shark was able to fight it off because of his animal nature. Now that they've developed the crown, Grodd has stolen it. It will amplify his powers a thousand-fold, letting him control the entire city.
Sherloque approaches Tanya as she watches Shay on the balcony. The detective notes that her hesitation occurred before Shay started to transform, and suggests that Tanya is frightened of seeing the face of the man that she loves. Tanya insists that they're friends, and Sherloque points out that she left a high-paying job for a man on another Earth and has been with him every moment. She says that it would be crazy to fall in love with her dead husband's doppelganger from another Earth. Sherloque points out that he married five different women from other Earths, and tells Tanya that the face may not matter that much if love is involved.
Tanya goes over to Shay, who says that when he was Shark his world was dull and gray until he met Tanya. She admits that she was avoiding Shay but isn't anymore, and assures him that she's not disappointed in him now that he's human. After a moment they kiss.
Joe takes Iris to the station lab and tells her to take her frustrations out on a punching bag. He explains that he went to Tibet to heal and went with Cecile's permissions. Joe has Iris start punching the bag, telling her to break "Cicada". She punches the bag harder until she knocks it back, and Joe chuckles.
The team spot Grodd heading up Broome Tower, the epicenter of Central City. Grodd takes control of every civilian, bending them to his will.
Killer Frost refuses to let Caitlin try to talk to Grodd. Cisco confirms that there are some anti-mind-control headsets but they didn't work so well the last time. Barry tells Nora to run at Grodd as fast as she can while he tries an old trick.
The dampener-wearing speedsters confront Grodd and Flash knocks him into a parking garage while XS keeps him distracted. Grodd recovers and blasts them back. Shay tells them to transform him back to Shark, making him immune to Grodd's mind control. Caitlin admits that they can do it but warns that it will prevent the cure from working on him again. Tanya tells Shay that he'll never be human again, but Shay says that it will let him help make up for the terrible things that he's done. Now they need a vibrational jolt to reverse the cure.
Grodd climb up out of the parking garage.
Cisco blasts Shay, who turns back into Shark.
Grodd paralyzes everyone in the city, and Shark breaches there and attacks Grodd. They fight and fall through an abandoned building. they fight throughout the building and emerge on the roof, and Grodd knocks Shark unconscious and ties him up upside down. Grodd then climbs up on a crane and continues using the helmet.
Flash and XS recover and see the unconscious Shark, and Tanya explains that a shark enters tonic immobility when turned upside down. They need electricity to wake him up, and Flash and XS generate lightning with their speed and hit Shark with it. Grodd is shocked as well, losing his mental control, and falls to the street. Shark lands nearby and attacks Grodd, glowing with electricity. He knocks Grodd down, removes the crown, and dons it himself.
Later at STAR Labs, Lyla tells the team that they've put Grodd in a medical coma. His powers are growing but as long as he's unconscious he can't access them. Barry wonders how they convinced Shay to turn back into Shark, and they tell him that he volunteered.
Sherloque finds Tanya watching Shark in an aquarium. Tanya wonders how it will affect their relationship, and Sherloque assures her that the two of them will figure it out. She thanks Sherloque for his advice, and he says that where Shay is man or shark or man-shark, the heart wants what the heart want and Tanya should be open to that. Tanya hopes that one day he finds what he's looking for with another doppelganger and they hug. Once Sherloque leaves, Tanya tells Shark that they found each other. He assures her that they're connection is still there, and tells her that he would do what he did again for her... his love.
Iris goes to her office, braces herself, and enters. She gets a news report about Grodd fighting Shark and complains that she missed it.
Barry asks Cisco and Caitlin if they're good, and admits that he deserved them attacking him. He promises that he won't use the cure as a weapon again, and his friends accept his apology. Caitlin points out that they know the cure works and they can use it to help all of the meta. Barry suggests that they should offer the cure to Cicada.
Written by Gadfly on Mar 6, 2019