Dr. Wells unleashes Grodd on the city to distract Barry and his team who are dealing with Reverse Flash's latest threat. Joe, Barry and Cisco pursue Grodd into the sewers, but the gorilla kidnaps Joe.The Flash
Scientist Barry Allen acquires super speed through a freak accident and becomes known as the Fastest Man Alive in this adaptation of the DC Comics character.
Dr. Wells unleashes Grodd on the city to distract Barry and his team who are dealing with Reverse Flash's latest threat. Joe, Barry and Cisco pursue Grodd into the sewers, but the gorilla kidnaps Joe.Barry, Caitlin, Cisco and Joe set a trap for Wells, but it puts Cisco in grave danger. Meanwhile, Eddie makes a decision regarding Iris, which unsettles Joe.Joe and Cisco head to Starling City to continue their investigation of Dr. Wells. While in town, Cisco meets the Black Canary, who asks him for a favor. Meanwhile, Barry races to catch a meta-human who can transform himself into any person he touches, including the Flash.A copycat killer known as the Trickster sets off bombs in Central City. In an effort to stop him, Barry and Joe seek help from the original Trickster, a criminal mastermind who has been imprisoned for 20 years. Meanwhile, Iris asks Eddie to help with a case. In flashbacks, Harrison Wells is shown coming up with the idea for the particle accelerator.The Flash learns that Captain Cold and Heat Wave have returned to Central City, and that Snart has brought along his sister Lisa to help wreak havoc on the town.The Weather Wizard appears in Central City to avenge his brother's death and targets Joe, who shot the man. Meanwhile, Cisco recalls the night when the team captured the Reverse Flash and realizes something doesn't add up; and Barry and Linda go on an awkward double date with Eddie and Iris.A nuclear explosion separates Ronnie and Dr. Stein. When General Eiling targets Firestorm, the two must decide whether they are safer together or apart. Meanwhile, Mason Bridge tells Iris that something secret is going on at S.T.A.R. Labs; and Stein gives Barry some important information about time travel.Dr. Wells' former protégé, Hartley Rathaway, returns to seek revenge on his mentor after being affected by the particle accelerator explosion. Meanwhile, Iris is hired as a cub reporter; Cisco recalls his first day on the job at S.T.A.R. Labs when he met Hartley and Caitlin; and Joe asks Eddie for a favor but asks him to keep it a secret from Barry.Captain Cold and his hotheaded partner Heat Wave plot to steal a multi-million dollar painting and try to lure the Flash into a battle of fire and ice by kidnapping someone close to him. Meanwhile, Barry asks Dr. Wells, Caitlin and Cisco to double his training efforts so he is ready when the Reverse Flash returns; and Iris deals with the aftermath of Barry's confession.Barry faces his nemesis Reverse Flash, who killed his mother, and plots with Wells and Cisco to trap him. Meanwhile, Eddie gives Iris a surprising gift at Christmas and leaves her with a question that could change her life.