Doctor Who: Logopolis
Directed by Peter Grimwade
Plot
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.
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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)
Peter Davison
The Doctor
Peter Pratt
The Master (archive footage)
Bruce Purchase
The Captain (archive footage)
Michael Wisher
Davros (archive footage)
Valentine Dyall
The Black Guardian (archive footage)