Arthur Darvill, best known as the companion of the Doctor's Companion Amy Pond, has joined the increasingly busy Arrow/Flash spinoff as Rip Hunter, a lesser-known time-traveling DC superhero. So two things of note here: 1) it looks like Booster Gold isn't part of the show, and 2) more Rory!
The choice for DC to include Rip Hunter instead of the better-known time-traveling superhero Booster Gold is a strange one, though. It makes me wonder if — and this is 100% speculation on my part — DC/WB might be saving the character as one with the potential to anchor his own TV series. Of course, for a certain period of time in the comics, Rip Hunter was Booster Gold's son from the future (and maybe he still is? I dunno), so maybe Booster will be showing up in the spinoff at some point down the line? Maybe?
Anyways, for those keeping track at home, that leaves only one of the show's mystery roles left to be filled. Here's the original description of the remaining character:
"MYSTERY HERO" | An African-American male in his twenties will fill the role of a regular, street smart guy who unexpectedly gains powers, and then, as part of the team, regularly quips about the insanity of the situations.
So, with Mystery Hero left to go, your Flash/Arrow spinoff League roster is: The Atom, Firestorm and Dr. Stein, Hawkgirl, Black Canary, Captain Cold, and Heatwave. Although Deadline suggests that Caity Lotz, who played originally Black Canary, might actually be on the show as a new character, for reasons that should be reasonably clear if you're caught up on Arrow. So maybe there's two more superheroes left to reveal after all...
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