Cast Credits Blackadder (1983) Guest starring as Angus, A Lord Episode 1x05: Witchsmeller Pursuivant (Jul 13, 1983) The Hitch Hiker's Guide to the Galaxy (1981) Guest starring as Deep Thought Episode 1x04: Episode 4 (Jan 26, 1981) Secret Army (1977) Starring as Dr. Pascal Keldermans Doctor Who (1963) Guest starring as Black Guardian (14 episodes) Episode 20x20: Enlightenment, Part Four (Mar 9, 1983) Episode 20x19: Enlightenment, Part Three (Mar 8, 1983) Episode 20x18: Enlightenment, Part Two (Mar 2, 1983) Episode 20x17: Enlightenment, Part One (Mar 1, 1983) Episode 20x16: Terminus, Part Four (Feb 23, 1983) Episode 20x15: Terminus, Part Three (Feb 22, 1983) Episode 20x14: Terminus, Part Two (Feb 16, 1983) Episode 20x13: Terminus, Part One (Feb 15, 1983) Episode 20x12: Mawdryn Undead, Part Four (Feb 9, 1983) Episode 20x11: Mawdryn Undead, Part Three (Feb 8, 1983) Episode 20x10: Mawdryn Undead, Part Two (Feb 2, 1983) Episode 20x09: Mawdryn Undead, Part One (Feb 1, 1983) Episode 16x26: The Armageddon Factor, Part Six (Feb 24, 1979) Episode 16x21: The Armageddon Factor, Part One (Jan 20, 1979) View 11 more View 11 less