Doctor Who: Logopolis (1981)

Director: Peter Grimwade

After an encounter with the Master, an airline stewardess named Tegan Jovanka becomes an unwitting stowaway aboard the TARDIS as it travels to the planet Logopolis. There, the Doctor discovers that the Master's interference with the Logopolitans' advanced mathematics has unleashed a wave of entropy which threatens to consume the entire universe.

Cast

Tom Baker

The Doctor

Matthew Waterhouse

Adric

Sarah Sutton

Nyssa

Janet Fielding

Tegan Jovanka

Anthony Ainley

The Master

Delore Whiteman

Aunt Vanessa

Tom Georgeson

Detective Inspector

John Fraser

The Monitor

Christopher Hurst

Security Guard

Adrian Gibbs

The Watcher (uncredited)