Orphaned by tragedy and raised by his best friend's father, brilliant CSI Barry Allen gains powers when lightning strikes him during a freak storm; when another meta-human attacks the city, Barry puts his powers to the test.

Barry experiences a setback while pursuing robbers; Joe is upset with Barry for taking the law into his own hands; Iris becomes more intrigued by the "red streak."

Barry and the team track The Mist -- a dangerous new meta-human with toxic gas powers; Joe decides to visit Henry in jail; Eddie and Iris continue to conceal their relationship.

A villain named Leonard Snart (Wentworth Miller) gets his hands on a "cold" gun -- which could kill Barry; Joe gives Iris the silent treatment.

Gen. Eiling (Clancy Brown) and the Army take over the case after a bomb goes off downtown, drawing Joe's suspicion; after refusing to stop writing about "the streak," Iris receives a visit from the Flash.

The Flash faces a new meta-human named Tony (guest star Greg Finley)who can turn himself into girded steel at will. While Dr. Wells and Caitlin are concerned about Barry's safety, Cisco comes up with a plan to take Tony (aka DC Comic villain Girder) down. Meanwhile, Iris's blog on The Flash gets her into trouble, and Eddie witnesses Tony's abilities firsthand and begins to ask questions that Joe doesn't want answered. Joe asks Dr. Wells to help him solve Nora Allen's murder.