The Edge of Destruction

The Edge of Destruction is the third serial of the British science fiction television series Doctor Who. It was written by David Whitaker, and first broadcast on BBC TV in two weekly parts on 8 February and 15 February 1964. The first episode was directed by Richard Martin, while Frank Cox directed the second. In the story, the Doctor, his granddaughter Susan, and her teachers Ian Chesterton and Barbara Wright are in the Doctor's time and space machine the TARDIS when it appears to be taken over by an outside force. The travellers begin acting strangely and turn against each other.