The veteran actor will be playing General Wade Eiling, often known as simply The General in the DC comic book world.
In the show, Eiling will be heading up a black ops army team who are in pursuit of Kelly Frye's Plastique in the hope of using her as a human weapon.
Clancy Brown has played various army and authoritarian roles in the past, playing Captain Hadley in The Shawshank Redemption and Sargent Zim in Starship Troopers as well as noteworthy villains like The Kurgan in Highlander and Brother Justin Crowe in HBO's Carnivàle (a personal favorite of mine).
Brown is also no stranger to comic book roles, having played Red Hulk, Lex Luthor, Odin and Taskmaster in a long string of voice-acting roles.
The Flash airs in the US on October 7, details for the UK are unknown at this time.
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