Casting is well underway for "Robots of Sherwood," and it appears the Mark Gatiss-penned episode will feature Ben Miller as a new villain.

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The well-known comedian will be showing off a more sinister side for the third episode of season 8, although further details about Miller's character have not been released.

"Mark Gatiss has written us a storming villain for his new episode, and with Capaldi in the TARDIS, we knew we needed somebody special to send everybody behind the sofa," explained showrunner Steven Moffat, according to the BBC. "And quite frankly, it's about time Ben Miller was in Doctor Who!"

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For his part, Miller is quite excited to be stepping behind the scenes of Britain's most iconic sci-fi series.

"As a committed Whovian I cannot believe my luck in joining the Twelfth Doctor for one of his inaugural adventures," Miller told the BBC. "My only worry is that they'll make me leave the set when I'm not filming."

Gatiss, however, is no stranger to the world of Time Lords and sonic screwdrivers. Co-creator of Sherlock and frequent collaborator of Moffat's, Gatiss' has written six episodes of Doctor Who ranging as far back as season 1's "The Unquiet Dead."

"Robots of Sherwood" will also feature Trevor Cooper, Ian Hallard, David Benson, Roger Ashton-Griffiths, Sabrina Barlett, and Tom Riley, according to Doctor Who TV.

Doctor Who will return to the BBC and BBC America later this year. Click the video below to get a sneak peek at the premiere episode.