Peter Davison

The Doctor

Sarah Sutton

Nyssa

Janet Fielding

Tegan Jovanka

Anthony Ainley

The Master / Kalid

Nigel Stock

Professor Hayter

Richard Easton

Captain Stapley

Keith Drinkel

Flight Engineer Scobie

Michael Cashman

First Officer Bilton

John Flint

Captain Urquhart

Judith Byfield

Angela Clifford