Per Deadline, Ninth (and best) Doctor Christopher Eccleston will be playing Dark Elf King Malekith the Accursed in Thor: The Dark World. This was the role Mads Mikkelsen was originally cast for, then dropped out of.
That first season when Doctor Who came back, halfway through, the British tabloids ran stories that Eccleston would be leaving by the Christmas Special, and eventually the BBC confirmed this, and announced David Tennant as his replacement. My favorite rumor at the time was that Eccleston wasn’t the Doctor at all, but the Master – either delusional from the Time War, or purposely impersonating his nemesis. There was the running “Bad Wolf” theme in the show that might back that idea up, and Eccleston was so nuanced as the Doctor, that right up until the end, it would’ve been completely believable for him to have been revealed as evil or insane.
Also, his season ended the same day Batman Begins opened, and i remember that summer there were many campaigning to get Eccleston cast as the Joker. So i’m quite glad he finally gets to be a proper villain in a big budget, comic book adaptation (don’t know if Destro counts?)