Matt Smith, best known for his role as the Eleventh Doctor in Doctor Who, has been cast for an unknown role in the new Terminator reboot, Paramount Pictures and Skydance Productions announced today.
The specific character Smith will play has not been released, just that he will "play a new character with a strong connection to John Connor."  Deadline reported the role as a major one "that will grow in the second and third films."
Smith joins a cast that includes Emilia Clarke as Sara Connor (see "'Game of Thrones' Star is New Sarah Connor"), Jason Clarke (Zero Dark Thirty) as John Connor, Jai Courtney (Divergent) as Kyle Reese,  Dayo Okeniyi  as Danny Dyson (son of the genius cyborg developer from Terminator: Judgment Day), Sadrine Holt (House of Cards) as Detective Cheung, and Arnold Schwarzenegger returning in his signature role.
The first film of the planned trilogy is titled Terminator: Genesis, and is directed by Alan Taylor.  The film currently has a release date of July 1, 2015.