The Doctor - Tom Baker
Leela - Louise Jameson
Dr. Fendelman - Denis Lill
Maximillian Stael - Scott Fredericks
Thea Ransome - Wanda Ventham
Adam Colby - Edward Arthur
Martha Tyler - Daphne Heard
Jack Tyler - Geoffrey Hinsliff
Ted Moss - Edward Evans
David Mitchell - Derek Martin
Hiker - Graham Simpson