Doctor Who's Twelve has seen his 'attack eyebrows' on another body, and the Time Lord is on the cusp of remember exactly where he's seen his currant visage before.

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In fact, Peter Capaldi's Doctor will dive into his complicated past when Game of Thrones' Maisie Williams joins the cast for episode 4, "The Girl Who Died."

Set to air on Oct. 17, the two-part episode will cause Twelve to reflect on his Torchwood and Pompeii adventures.

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"In a backwater of history, in a little Viking village where all the warriors have just been slaughtered, a young girl called Ashildr is about to make a desperate mistake," The Radio Times teased. "The Mire are the deadliest mercenaries in the galaxy, famed for being unstoppable and without mercy - and Ashildr has just declared war on them. The Doctor and Clara have twelve hours to turn a handful of farmers and blacksmiths into a fighting force ready to face down Odin himself. And there's more - because this is the day when the Doctor remembers where he's seen his own face before."

Will viewers be treated to flashbacks to Capaldi's various pre-Doctor adventures in the Who-verse? Will we finally find out what piece of Time Lord DNA dictates each regeneration's looks?

Find out more when Doctor Who airs Saturdays on the BBC and BBC America. Click the video below to see a preview for season 9's next episode, "Before the Flood."

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