Barry Allen is a police scientist with a reputation for being very slow, deliberate, and frequently late, which frustrates his fiancee, Iris West. One night, as he is preparing to leave work, a lightning bolt shatters a case full of chemicals and spills them all over Allen, granting him super speed ability which he uses to battle against the forces of evil.
- Barry Allen/Flash II (Bradley Cooper) - a police scientist, and a fan of the Golden Age Flash, he became struck with the chemicals from a lightning bolt from the Weather Wizard, he was later mentored by Jay Garrick to control his speeding powers and vibrations, and became the Silver Age Flash, he gained media attention, but became very serious when danger comes, in the end, hears about Captain Cold.
- Iris West (Jessica Chastain) - Barry's fiancé, who become frustrated with Barry being late, until she becomes supportive of her fiancé, in the end, appologizes for her selfish reasons and gain a kiss from Barry.
- David Singh (J.K. Simmons) - Barry's boss, who isn't fond of him being late, in the end, realizes the Flash's identity and starts understanding.
- Patty Spivot (Charlize Theron) - Barry's partner in the lab, in the end, was killed by Zoom.
- Eobard Thawne/Zoom (Steve Buscemi) - the primary antagonist and Barry's mentor for science, he orcastrated Barry to be dead by Weather Wizard, but he witnessed Barry having speed powers, his goal is to create a wormwole, in this version, Zoom is born in the 1950's, instead of the future, in the end, he disintagrated during hyperspeed.
- Mark Mardon/Weather Wizard (Michael Eklund) - he became a criminal obsessed with creating storms, he caused the creation of the Flash, when Barry doubted as the Silver Age Flash, Mardon was doublecrossed by Thawne and was arrested.
- Jay Garrick/Flash (Burt Reynolds) - the Golden Age Flash, who later retired to spend more time with his wife, Joan, he taught Barry how to be a speedster, in the end, he teaches Barry one more thing while battling Zoom, the Speed Force, as Jay Shows him the hyperspeed which Zoom doesn't survive.