Guest Stars Nicholas Courtney as Alistair Gordon Lethbridge-Stewart Richard King as Cyberman Pete Thornton as Cyberman Pat Gorman as Cyberman Ralph Carrigan as Cyberman Charles Finch as Cyberman John Spradbury as Cyberman Peter Halliday as Packer Kevin Stoney as Tobias Vaughn Sally Faulkner as Isobel Robert Sidaway as Captain Turner James Thornhill as Sergeant Walters Edward Burnham as Professor Watkins Clifford Earl as Major Branwell Norman Hartley as Sergeant Peters
