The TARDIS arrives in London in 1966 and the First Doctor and Dodo visit the Post Office Tower. There they meet Professor Brett, whose revolutionary new computer WOTAN (Will Operating Thought ANalogue) can actually think for itself and is shortly to be linked up to other major computers around the world — a project overseen by civil servant Sir Charles Summer.
William Hartnell
as The Doctor
Jackie Lane
as Dodo Chaplet
Anneke Wills
as Polly
Michael Craze
as Ben Jackson
John Harvey
as Professor Brett
John Cater
as Professor Krimpton
William Mervyn
as Sir Charles Summer
Alan Curtis
as Major Green
Gerald Taylor
as War Machine Operator/The Voice of WOTAN
Sandra Bryant
as Kitty
Ewan Proctor
as Flash Customer
George Cross
as The Minister
