The Sound of Drums: Part one of two. The mysterious Harry Saxon seizes his opportunity to begin a reign of terror when he becomes prime minister and announces human contact has been made with an alien race called the Toclafane. Guest starring John Simm, McFly, Sharon Osbourne and Ann Widdecombe.
With David Tennant, Freema Agyeman, John Barrowman, Adjoa Andoh, Gugu Mbatha-Raw, Trevor Laird, Reggie Yates, Alexandra Moen, Colin Stinton, Nichola McAuliffe, Nicholas Gecks and Olivia Hill.
On next: Saturday 23rd June on BBC 1 London at 7:15p.m.