He's stood looking to the side in a room with artwork on the walls in the Rachel Talalay-directed episode, with a clapperboard in the forefront of the image.
Doctor Who's official account on Twitter, which was recently rebranded as X, teased there's more behind-the-scenes looks to come, adding: "Welcome to #WhoSpy! I'll be your very own spy on set during filming of #DoctorWho, keep your eyes peeled for more updates."
Fans can't wait to see Doctor Who legend Tennant back for more, alongside the great Catherine Tate, who's returning as Donna Noble.
The Star Beast is the first of the specials to come in November, and will be followed by The Giggle and Wild Blue Yonder.
She also teased that her one is action-packed, revealing: "My episode features lots of people in lots of scenes. There’s soldiers, there’s battles."
Directors Chanya Button and Tom Kingsley will direct the remaining two specials.
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