The Doctor gets a Stetson (and a gun!), and finds himself the reluctant Sheriff of a Western town under siege by a relentless cyborg named Gunslinger. But who is he and what does he want? CAST: Matt Smith

Press Release:
The Doctor gets a Stetson (and a gun!), and finds himself as the reluctant Sheriff of a Western town which is under siege from a relentless cyborg (who goes by the name of Gunslinger). But who is Gunslinger and what does he want?

The answer seems to lie with the mysterious, Kahler-Jex, an alien doctor (yes another one!) whose initial appearance is hiding a dark secret.

PRODUCTION DETAILS:
A BBC Production. Executive Produced by Steven Moffat and Caroline Skinner, Written by Toby Whithouse, Directed by Saul Metzstein, Produced by Marcus Wilson