According to ComicBook, 12 Monkeys actor Demore Barnes has joined the cast of Flash season 2 as Henry Hewitt, better known in comic books as the Firestorm villain Tokamak.
It's unclear whether Hewitt will function as a villain in Flash, as CW describes him as "a charming, but cocky scientist who was affected by the same Particle Accelerator explosion that created the Flash. When Caitlin Snow recruits him to join the team at S.T.A.R. Labs, Hewitt jumps at the opportunity to fulfill his destiny as a powerful meta-human."
In comic books, Hewitt was a malicious scientist who tried to blackmail the U.S. government, and was responsible for the creation of Firehawk, a female supehero with powers that resembled those of Firestorm.
Flash season 2 premieres October 6 on CW.