After a particle accelerator causes a freak storm, CSI Investigator Barry Allen is struck by lightning and falls into a coma. Months later he awakens with the power of super speed, granting him the ability to move through Central City like an unseen guardian angel. Though initially excited by his newfound powers, Barry is shocked to discover he is not the only "meta-human" who was created in the wake of the accelerator explosion -- and not everyone is using their new powers for good. Barry partners with S.T.A.R. Labs and dedicates his life to protect the innocent. For now, only a few close friends and associates know that Barry is literally the fastest man alive, but it won't be long before the world learns what Barry Allen has become...The Flash!
Barry and Iris discover that they're having communication issues and go in for couples therapy... just as a new meta starts targeting tech billionaires. Meanwhile, Cisco inadvertently blows off a special day for Gypsy.
The team goes up against the second of the Thinker's metas: Becky Sharpe, aka Hazard, who can gain good luck for herself as long as everyone else suffers. Meanwhile, Cecile suggests to Joe that they buy a new house, and Iris tries to plan the wedding.
While looking for the bus passengers, Barry and Joe come across Ralph Dibny, a former cop who was fired from the force and gained a.... unique power from the dark matter. Meanwhile, Gypsy's father Breacher comes to see his daughter's new boyfriend Cisco, and soon starts hunting him.
The guys and girls throw separate parties for Barry and Iris. While Barry gets drunk with some help from Cisco and Ralph takes them to a strip club, the ladies get involved with Killer Frost when her former boss, Amunet, demands that Killer Frost return to work for her.
Flash and Elongated Man team up to fight one of the Thinker's metas, a Sioux Indian woman calling herself Black Bison that is hunting down the three pieces of an artifact. Meanwhile, Harry calls together three of his counterparts to form the "Council of Wells" and figure out who DeVoe is.
When Wolfe offers Barry and the bus metas to Blacksmith, Barry engineers an escape for all of them. Meanwhile, Ralph has a crisis of faith when an old "friend" tells him that he eventually fails everyone who counts on him.
A terrorist detonates a nuclear bomb, and Flash must race between microseconds to try and stop it. Jesse and Jay lend their speed to his efforts, but even the three of them aren't fast enough to stop a nuclear explosion that has already happened.
Iris accidentally takes Barry's speed when a new meta with the power to swap powers touches both of them. Now they have to learn how the other half lives as Iris takes to the field and Barry monitors events. Meanwhile, Ralph refuses to leave S.T.A.R. Labs for fear that Clifford will kill him, and Harry undertakes a dangerous experiment to match their opponent's augmented intellect.