For most of Season 2 of "The Flash," Barry has been concerned with sinister speedster Zoom (Tony Todd), a super villain from Earth 2. However, in episode 7, "Gorilla Warfare," the Flash does not need another universe to find a foe strong enough to warrant his attention. In fact, one of Barry's oldest enemies returns -- Grodd (David Sobolov).
When the episode begins, Barry is recovering from his Zoom injuries quickly, but he is still without his speed -- or use of his legs at all, for that matter. With the Flash out of commission, Caitlin gets a little nervous about Dr. Wells (Tom Cavanagh) leaving. The disappointed doctor wants to return to Earth 2 to hunt for Zoom alone, but Caitlin thinks their best chance at stopping the super villain is working together. She convinces him to stick around when they come up with a plan to close every breach between the two universes except the one in S.T.A.R. Labs, where they can set a trap for Zoom.
Meanwhile, Cisco (Carlos Valdes) goes on his date with Kendra Saunders (NAME) -- he takes her to the movies! However, when she tries to hold hands he gets an intense Vibe where he sees an angelic silhouette in a blinding light of a figure dressed in an hawk suit. Unaware that his hot date will eventually become Hawkgirl -- only fans know that right now -- he gets spooked and stops the date short.
Elsewhere, a lab gets robbed of some intelligence-enhancing drugs when a seemingly mind-controlled scientist. It's Grodd! The next day, Joe (Jesse Martin) and Patty (Shantel VanSanten) find hairs and send them off to the lab for analysis.
Meanwhile, Barry is dealing with some problems, even though he has his legs back. For one thing, he is lying to Patty and telling her that the reason he can not see her is that he is sick. She is not buying it. Plus, on top of his physical setbacks, he is going through a crisis of confidence. Having been so thoroughly beaten by Zoom for all of Central City, he does not think anyone believes in him anymore. Joe tries to comfort him, but nothing is working.
Then, Joe (Jesse Martin) gets a phone call from Patty telling him that she just got the analysis back on those hair samples they found from the scene of a robbery where a stash of intelligence-enhancing drugs were stolen -- sound like Grodd? She says there is something strange about the samples, though. They are not human hair. Joe knows what is going on immediately and cuts her off -- "They are from a gorilla." Patti is left wondering how Joe seems to already know who they are looking for, while Joe runs off to warn Barry and Cisco (Carlos Valdes).
He's too late. Grodd tapped into Caitlin's mind and led the scientist out of S.T.A.R. Labs before kidnapping her and taking her into the sewers. He wants her to help engineer more super smart gorilla babies.
Back at S.T.A.R. Labs, Barry is still in the dumps about having let the city down. Luckily, Iris (Candice Patton) has the perfect fix. She tracks down Henry (John Wesley Shipp) and Barry gets to see his father for the first time since the premiere. Henry gives Barry a pep talk, comparing what Barry is going through to having had everyone believing he was a murderer.
"Sometimes you just have to slow down," Henry tells his son.
It works! Barry cheers up and gets on the radio to help Wells and Cisco, who have gone to rescue Caitlin.
Using an old Reverse Flash suit, Wells hopes to distract Grodd long enough to get Caitlin to safety. Things start off smoothly enough, as Grodd immediately recognizes Wells as "father." However, when Wells acts a little too nice to be the Earth 1 Wells, Grodd gets suspicious and springs into attack mode. Things get a little hairy, but Wells is able to inject Grodd with an overdose of his intelligence-boosting drugs, temporarily paralyzing the giant gorilla and allowing them to escape.
It is still a problem to have Grodd laying in wait in Central City, though, so the S.T.A.R. Labs team comes up with a new plan. This time, Barry conquers his fears and act as the bait to draw Grodd into one of the breaches and send him to a wildlife refuge Wells told them about over on Earth 2. The Flash takes a beating at first as his Zoom-layover fears cause him to freeze up, but he eventually rises to the occasion knocks Grodd into the breach.
Barry is feeling good again after the battle with Grodd and with Peter Gabriel's "In Your Eyes" serving as the soundtrack he goes and makes up with Patty, where he apologizes for keeping her in the dark about why he had been unavailable -- Although, he still lies and says it was because of his dad.
Meanwhile, Cisco completes the "Say Anything" connection with "In Your Eyes" when he holds up a basket of flowers and chocolates John Cusack-with-a-boom-box-style to apologize to Kendra. He wins her over and even gets a kiss. It is a pretty intense kiss and not just because Cisco is finally get a win in the romance department. He gets another vibe of the hawk-like figure from earlier, but this time it is clearly Kendra -- Foreshadowing!
Then, in the episode's last scene, fans got a glimpse of Grodd's new home -- Gorilla City!