- Martin Landau
- Commander John Koenig
- Barbara Bain
- Dr. Helena Russell
- Catherine Schell
- Maya
- Tony Anholt
- Tony Verdeschi
- Nick Tate
- Alan Carter
- Zienia Merton
- Sandra Benes
- Brian Blessed
- Mentor
- Anouska Hempel
- Annette Fraser
- Jeffery Kissoon
- Dr. Ben Vincent
- Peter Porteous
- Petrov
- Tony Osoba
- 1st Security Guard
- John Judd
- 2nd Security Guard
- Trevor Thomas
- Refuel Eagle Pilot
- Andrew Lodge
- Grasshopper
- John Hug
- Bill Fraser
- Gerard Paquis
- Lew Picard
- Nick Brimble
- Ray Torens
- Anton Phillips
- Dr. Bob Mathias
- Sarah Bullen
- Main Mission Operative Kate Bullen
- George Lane Cooper
- 1st Overseer
- John Dixon
- Small Alien
- Christopher Figg
- Alphan
- Nick Hobbs
- 5th Security Guard
- Alf Joint
- 2nd Overseer
- Jack Klaff
- 4th Security Guard
- Reuben Martin
- Gorilla
- Neil McCaul
- Zombie Alien
- Geoffrey Moon
- Short Alien
- Barry Morse
- Prof. Victor Bergman
- Quentin Pierre
- 3rd Security Guard
- Pam Rose
- Command Center Operative
- Roy Stewart
- Tall Alien
- Terry Walsh
- Technician
