Dominic Purcell, who plays the pyromaniac Heat Wave on the Flash, will join the cast of an as-yet-unnamed Arrow/Flash spin-off series that will likely debut on the CW network in midseason next year (see "CW Plans 'Arrow/Flash' Spin-off Show”), much as iZombie, which debuts tonight, is doing this year.  Purcell will team up with his co-star from the Prison Break series, Wentworth Miller, who plays Leonard Snart/Captain Cold on the Flash.

Purcell and Wentworth, who teamed up on the Flash, are joining a cast for the new Arrow/Flash spin-off that also includes Brandon Routh, who plays Ray Palmer/The Atom on Arrow, Victor Garber, who plays Dr. Martin Stein on Flash, and Caity Lotz, who played Sara Lance/Black Canary on Arrow.  Since Sara Lance was killed, and her sister Laurel (played by Katie Cassidy) became Black Canary, it is not at all certain who Caity Lotz will play in the spin-off series.  Also Robbie Amell, who "combined" with Dr. Martin Stein on Flash to create Firestorm, will not, according to Deadline, participate in the new series, so it will be interesting to see how the Dr. Martin Stein character will be handled in the new spin-off.