• 
  Bob Brooks

  regizor

• 
  Tony Barwick

  scenarist

• 
  Ian McShane

  Anton Zoref
• 
  Christopher Lee

  Captain Zandor (1 episode, 1976)
• 
  Martin Landau

  John Koenig
• 
  Barbara Bain

  Dr. Helena Russell
• 
  Nick Tate

  Alan Carter
• 
  David Prowse

• 
  Jan Harvey
• 
  Kevin Stoney

  Talos (1 episode, 1976)
• 
  Geoffrey Bayldon

  Number Eight (1 episode, 1976)
• 
  Shane Rimmer

  Eagle Pilot  (5 episodes, 1975-1976)
• 
  Paul Jerrico

  1st Security Guard (1 episode, 1977)
• 
  Billie Whitelaw

  Zamara (1 episode, 1976)
• 
  Jill Townsend

  Sahala (1 episode, 1977)

• 
  John Shrapnel

  Capt. Jack Tanner (1 episode, 1975)
• 
  Bernard Kay

  Humanoid (1 episode, 1976)
• 
  Ann Firbank

  Consul Varda (1 episode, 1978)
• 
  Orso Maria Guerrini

  Luke Ferro (1 episode, 1976)
• 
  Oliver Cotton

  Spearman (1 episode, 1976)
• 
  Joan Collins

  Kara (1 episode, 1975)
• 
  Neil McCaul

  Alien in cave (1 episode, 1976)
• 
  Judy Geeson

  Regina Kesslann (1 episode, 1976)
• 
  Cassandra Harris

  Controller  (1 episode, 1977)
• 
  Jack Klaff

  Guard (1 episode, 1976)
• 
  Brendan Price

  Security Guard (1 episode, 1976)
• 
  Alex Scott

  Aarchon (1 episode, 1975)
• 
  Nadim Sawalha

  Zoran (1 episode, 1977)
• 
  Maxine Audley

  Theia (1 episode, 1976)
• 
  Anthony Nicholls

  Dr. James Warren (1 episode, 1976)
• 
  Douglas Wilmer

  Commissioner Dixon (1 episode, 1975)
• 
  Vincent Wong

  Medic  (4 episodes, 1975-1976)
• 
  Angus MacInnes

  Jelto (1 episode, 1977)
• 
  Julian Glover

  Jarak (1 episode, 1975)
• 
  Willoughby Goddard

  Taybor (1 episode, 1976)
• 
  Carolyn Seymour

  Eva (1 episode, 1977)
• 
  Cyd Hayman

  Cynthia Crawford (1 episode, 1975)
• 
  Pamela Stephenson

  Michelle Osgood (1 episode, 1976)
• 
  Gwen Taylor

  Nurse (1 episode, 1975)
• 
  Godfrey James

  Alien Transporter (1 episode, 1976)
• 
  Paul Weston

  Main Mission Operative  (3 episodes, 1975-1976)
• 
  Chai Lee

  Main Mission Operative  (4 episodes, 1975-1976)
• 
  Roy Dotrice

  Commissioner Simmonds (2 episodes, 1975-1976)
• 
  Catherine Schell

  Maya  (25 episodes, 1975-1978)
• 
  Leigh Lawson

  Zarl (1 episode, 1976)
• 
  Patrick Troughton

  Archon (1 episode, 1978)
• 
  Gay Hamilton

  Eva Zoref (1 episode, 1975)
• 
  Peter Bowles

  Balor (1 episode, 1976)
• 
  Norma West

  Main Mission Operative (1 episode, 1975)
• 
  Stuart Wilson

  Vindrus (1 episode, 1976)
• 
  Tony Osoba

  1st Security Guard (1 episode, 1976)
• 
  Valerie Leon

  Thule Girl (1 episode, 1975)
• 
  Trevor Thomas

  Refuel Eagle Pilot (1 episode, 1976)
• 
  Lee Montague

  Dorzak (1 episode, 1977)
• 
  Hildegarde Neil

  Elizia (1 episode, 1977)
• 
  Freddie Jones

  Dr. Charles Logan (1 episode, 1976)
• 
  Hilary Heath

  Laura Adams (1 episode, 1976)
• 
  Nicholas Campbell

  Eddie Collins (1 episode, 1976)
• 
  John Standing

  Pasc (1 episode, 1976)
• 
  Isla Blair

  Carla  (2 episodes, 1975-1976)
• 
  Barry Morse

  Prof. Victor Bergman (24 episodes, 1975-1976)
• 
  Stacy Dorning

  Zova (1 episode, 1976)
• 
  Gianni Garko

  Tony Cellini (1 episode, 1975)
• 
  Patrick Westwood

  Dr. Shaw (2 episodes, 1977)
• 
  Lisa Harrow

  Anna Davis (1 episode, 1976)
• 
  Vic Armstrong

  Main Mission Operative  (2 episodes, 1975-1976)
• 
  Jeffery Kissoon

  Dr. Ben Vincent (7 episodes, 1976-1977)
• 
  Billy J. Mitchell

  Professor Hunter (2 episodes, 1977)
• 
  Michael Halsey

  1st Dorcon Soldier (1 episode, 1978)
• 
  Leo McKern

  Companion Gwent (1 episode, 1976)
• 
  Philip Madoc

  Commander Gorski (1 episode, 1975)
• 
  Caroline Mortimer

  Dione (1 episode, 1976)
• 
  James Laurenson

  Patrick Osgood (1 episode, 1976)
• 
  Sarah Douglas

  B (1 episode, 1976)
• 
  Kathryn Leigh Scott

  Yesta (1 episode, 1977)
• 
  Michael Culver

  Pete Irving (1 episode, 1975)
• 
  Peter Cushing

  Raan (1 episode, 1976)
• 
  Giancarlo Prete

  Dan Mateo (1 episode, 1976)
• 
  Richard LeParmentier

  Ed Malcolm (1 episode, 1977)
• 
  Margaret Leighton

  Arra (1 episode, 1975)
• 
  Nick Brimble

  Ray Torens (1 episode, 1976)
• 
  Lynne Frederick

  Shermeen Williams (1 episode, 1976)
• 
  John Judd

  2nd Security Guard (2 episodes, 1976-1977)
• 
  Hazel McBride

  Female Medical Officer (1 episode, 1978)
• 
  Brian Blessed

  Dr. Cabot Rowland  (2 episodes, 1975-1976)
• 
  Roy Marsden

  Alien Invisible  (2 episodes, 1976-1977)
• 
  Jeremy Kemp

  Dr. Ernst Linden (1 episode, 1975)
• 
  Bernard Cribbins

  Captain Michael (1 episode, 1976)
• 
  Tony Anholt

  Tony Verdeschi
• 
  Sarah Bullen

  Operative Kate
• 
  Prentis Hancock

  Paul Morrow
• 
  Clifton Jones

  David Kano
• 
  Zienia Merton

  Sandra Benes
• 
  Anton Phillips

  Dr. Mathias