It looks like "Game of Thrones" star Maisie Williams's new "Doctor Who" character is just as much of a sassy smartass as Arya Stark. But who is she playing in "Doctor Who" Season 9? The new trailer was just released at Comic-Con, with Maisie featured briefly in the end in a mysterious scene with Peter Capaldi.

The Doctor: "You?"

Maisie's Character: "What took you so long, old man?"
Now fans are speculating on who this character might be. A younger version of Clara, Susan, River Song, or ... Other? Executive producer Steven Moffat didn't reveal much of anything at Comic-Con, just saying, "It's going to be surprising what she gets up to." Back in March, when Maisie's casting was announced, Steven said, "She is going to challenge the Doctor in very unexpected ways. This time he might just be out of his depth, and we know Maisie is going to give him exactly the right sort of hell."

Here's the trailer:



"Doctor Who" Season 9 premieres September 19 on BBC America. Do you have a theory on Maisie's character?

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