Guest Stars Anthony Ainley as The Master Richard Easton as Captain Stapley Keith Drinkel as Flight Engineer Scobie Michael Cashman as First Officer Bilton Judith Byfield as Angela Clifford Nigel Stock as Professor Hayter Mykel Mills as Plasmaton (uncredited) Peter Dahlsen as Horton Brian McDermott as Sheard Richard Bonehill as Flight Engineer (uncredited)