Despite not being able to feel his legs last week, Barry is now up and walking, with a little bit of help. The good news is he’s almost healed, and everyone at STAR is hopeful that maybe Zoom won’t be coming back, except for Harry who is eager to put a stop to Zoom by returning back to Earth-2. No one puts up a stink about him leaving, except for Caitlin, who thinks they still need his help. An alarm goes off to remind Cisco about his date that night and Barry’s phone rings. It’s Patty, who wishes him well while he’s sick, though she’s clearly suspicious of what he’s up to. At a bar, Harry marks points on a map and Caitlin comes to him offering their help in saving his daughter. Harry confides that he had one plan to stop Zoom, get The Flash’s help, and since that failed he has no back-up plan. Caitlin makes a snide comment about closing the breaches, setting off a light bulb over Harry’s head.
On the other side of town, Cisco takes Kendra to see The Princess Bride for their first date, a good choice, and when she takes his hand, he vibes, receiving a vision of an armored figure in the sky with a grand pair of wings. Freaked out, he leaves. In yet another part of town, a lab guy at a pharmaceutical company prepares to head home when familiar visions plant themselves in his head. He breaks into a room with his bare hands and pulls out a large container of chemicals. After taking it outside, he snaps out of the trance only to find Gorilla Grodd behind him. The next morning, Patty and Joe look over the crime scene and its many questions. Why this drug? How’d that guy hit his head way up there? Patty asks about Barry, too, and Joe does a bad job of covering for him, it’s almost cringe-inducing to hear.
Back at STAR Labs, Barry is walking better and even manages to pick up the pace, but he flashes back to his encounter with Zoom and tumbles off the treadmill. He may be getting his speed back, but Barry has lost his confidence. The city knows he’s not strong enough to protect them anymore. Meanwhile in the basement, Cisco asks Caitlin if she’s heard anything about Birdmen, which she answers with an eye roll. That familiar trance overcomes her and she slugs Cisco before leaving. Joe isn’t sure what to do about Barry, but manages to give Iris an idea. Patty calls with info about the crime scene, revealing the stolen drugs were used to enhance intelligence and that a weird type of hair was found, but Joe already knows what kind, gorilla hair. Joe and Cisco converge in the main lab where they finally say it out loud, Grodd is back. They watch the security camera footage as Caitlin walks out of the building, to be followed by the big ape himself.
The team tries to think of why Grodd would take Caitlin, prompting Wells to reveal that intelligent apes exist on his world too. Barry wants to blame himself for whats happened, but Harry tells him despite not having his powers, he still has one advantage, his mind. Elsewhere, Caitlin wakes up in a dingy lab where Grodd explains he needs her help. He wants her to make more like him. Barry goes back to running on the treadmill as his powers begin to manifest again, but they have a visitor, his father (Iris’ big idea). As Henry and Barry share some father/son time, Harry and Cisco are able to track Grodd’s location and come up with a very smart but very dumb plan, dress up Harry like the Reverse Flash and trick Grodd into letting Caitlin go. It’s so crazy it just might work.
With two of the three possibile locations a bust, Harry and Cisco approach the final bell tower, where Harry practices his best Earth-1 Dr. Wells impression. It’s pretty good! Barry waits in anticipation and cites his fears to his father, who reminds him how many people turned their backs on him and thought different of him when they thought he killed Nora. He embraced their hate though and young Barry gave him hope. No monster can take that from him. In the bell tower, Caitlin explains the process to Grodd when the door opens, and Harry steps in as Grodd’s “father.” He tries to convince him to let Caitlin go, but Grodd quickly sniffs out the ruse and knocks Harry across the room. Cisco leaps in and is able to save Caitlin, giving Harry time to find the nearby drugs that Grodd has stolen and allowing him the chance to stick the giant ape with them. The three escape (mostly) unharmed.
Back at STAR Labs, Caitlin patches up Harry, but everyone still thinks they need to take care of Grodd. Joe suggests killing him, but Caitlin defends the ape – he’s lonely and sad. These keywords ignite a thought in Harry’s mind, who knows where to send him, through the breach and to a specific location on Earth-2. All of the breaches on Earth-1 are scattered about Central City, but they’re all over the planet on Earth-2, so if they can find just the right one they can put Grodd wherever they want. Unsure how to do it, Henry volunteers Barry, giving him that extra confidence boost he needed. Caitlin draws out Grodd and Barry forces him into a chase to the spot where Cisco and Harry have set up the speedcannon. Grodd manages to catch Barry and give him a good wallop, but Caitlin is able to make him stop and lure him into the spot. The speedcannon begins the process of sending him to Earth-2, but it’s not strong enough. Henry gives Barry one last push over the radio, and the scarlet speedster punches the giant gorilla into a portal sending him into another world. Can we just take a minute to be amazed this is a thing that happened on TV?
Afterward, Team Flash is ready to get rid of the Reverse Flash suit, but Barry would love to figure out how to put his own costume in Wells’ old Flash Ring, which Harry offers to help with. Henry says his goodbyes to everyone and Cisco asks Harry where they sent Grodd, and he teases a refuge for gorillas subjected to experiments. Which leads to their next task at hand, closing the breaches to leave Zoom with just one door to Earth-1. At Joe’s house, Barry, Henry, Joe and Iris all talk over baby pictures before Henry prepares to leave town again. As they exit, Joe can’t help but feel sentimental over his time with Barry, especially when placed in a situation where he’s reminded he’s not actually his son. Iris tells him if he had his own son, he definitely would have done great with him. Don’t forget, he definitely has his own son, because Iris found out about it in episode 4.
Barry goes to see Patty at the CCPD to confess he wasn’t actually sick. He tells her that his father was in town, which still seems like the kind of thing that he should be able to tell her. Given Henry’s past, though, Barry was unsure. Patty lays down the law, she needs to know if she can trust him. As kissy time begins in the CSI Lab, Cisco goes to Jitters to make up for his ditched date with Kendra. He covers by telling her about his liaison job with the CCPD. Luckily he’s prepared a basket of goodies and brought a tiny projector so they can watch The Princess Bride. Kendra plants a kiss on him, giving Cisco the complete vibe – that winged figure was no man or angel, it was Kendra. Meanwhile on Earth-2, Grodd falls through the portal and finds himself in the jungle, a jungle with rocks cut into the shapes of gorillas, and a city below him, a gorilla city.