Despite a few recent clarifications from Arrow and Flash producers, we still have no idea what to expect from the forthcoming Atom-centric team-up spinoff. The latest casting doesn’t tip the scale either way, though Wentworth Miller’s Captain Cold will be relieved to have some company, as Prison Break brother Dominic Purcell joins the spinoff in his Heat Wave guise.

Deadline broke news that Purcell would rejoin Miller for the upcoming spinoff series, though we don’t quite know how the pair will fit into a cast that includes Brandon Routh’s Atom, Victor Garber’s Dr. Martin Stein, a seemingly-resurrected Caity Lotz, or at least three other heroes and villains. Purcell has thus far appeared in two Flash episodes as his Mick Rory / Heat Wave character, with a third due next week for “Rogue Time.”

Eyed for a midseason 2016 debut, the CW spinoff has also obscured whether a formal order of 23 episodes will join Arrow and The Flash, or if the untitled team-up series would act as a miniseries of sorts. Casting remains ongoing, as the new series seeks actors for a time-traveling hero, a booksmart Latina warrior, and wise-cracking African-American superhero.

Reticent though we are to see such superhero overload on The CW, does Dominic Purcell make a sensible addition to the spinoff? Who else from the existing Arrow-verse should join the team-up special? Check out Heat Wave’s return in The Flash trailer below, while we wait!

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