 | Charles 'Bud' Tingwell | ... | Capt. Jaffe / ... (3 episodes, 1965-1969) |
 | Peter Copley | ... | Charles Wilson / ... (3 episodes, 1965-1971) |
 | Geoffrey Palmer | ... | Chief Officer / ... (3 episodes, 1965-1971) |
 | Erik Chitty | ... | Bernard / ... (3 episodes, 1965-1969) |
 | Ronald Lewis | ... | Dr. Max Harrow / ... (2 episodes, 1965-1966) |
 | David Langton | ... | Dr. Morrison / ... (2 episodes, 1965-1966) |
 | James Maxwell | ... | Jonas Foster / ... (2 episodes, 1965-1966) |
 | Tom Criddle | ... | Doctor / ... (2 episodes, 1965-1966) |
 | Keith Buckley | ... | Scotty / ... (2 episodes, 1965-1966) |
 | Jessica Dunning | ... | Annika / ... (2 episodes, 1965-1966) |
 | Tony Wager | ... | Harvey / ... (2 episodes, 1965-1966) |
 | Geoffrey Kenion | ... | Birch / ... (2 episodes, 1965-1966) |
 | David Munro | ... | Ken / ... (2 episodes, 1965-1971) |
 | Anthony Bate | ... | General / ... (2 episodes, 1966-1971) |
 | Tenniel Evans | ... | QT-1 / ... (2 episodes, 1965-1967) |
 | Petra Davies | ... | Mary Birkett / ... (2 episodes, 1966-1969) |
 | Peter Barkworth | ... | Dr. Philimore / ... (2 episodes, 1969-1971) |
 | David Collings | ... | R. Daneel Olivaw / ... (2 episodes, 1966-1969) |
 | John Robinson | ... | Dr. Saint / ... (2 episodes, 1966-1969) |
 | Robert James | ... | Dr. Kersh / ... (2 episodes, 1965-1969) |
 | Peter Madden | ... | Spelman / ... (2 episodes, 1965-1966) |
 | Derek Benfield | ... | Dr. Moore / ... (2 episodes, 1969-1971) |
 | Clifford Cox | ... | Ewan McKenzie / ... (2 episodes, 1969-1971) |
 | Shirley Cain | ... | Frances Mervyn / ... (2 episodes, 1965-1971) |
 | Jerry Stovin | ... | Spaceship captain / ... (2 episodes, 1965-1966) |
 | Jane Jordan Rogers | ... | Voice of Friend / ... (2 episodes, 1966) |
 | David Cargill | ... | Radio man One / ... (2 episodes, 1966-1969) |
 | Raymond Hardy | ... | Radio man Two / ... (2 episodes, 1966-1969) |
 | Alan Downer | ... | John Sherwood / ... (2 episodes, 1969-1971) |
 | Michael Danvers-Walker | ... | Brett / ... (2 episodes, 1965-1966) |
 | Sebastian Breaks | ... | Paul Porter / ... (2 episodes, 1966-1971) |
 | Wendy Gifford | ... | Dr. Susan Calvin / ... (2 episodes, 1965-1969) |
 | Robert MacLeod | ... | American man / ... (2 episodes, 1965-1969) |
 | Milo O'Shea | ... | Henry Wilkes / ... (2 episodes, 1965-1969) |
 | John Gabriel | ... | Easterbrook / ... (2 episodes, 1965-1966) |
 | Patrick Scanlan | ... | Captor / ... (2 episodes, 1965) |
 | John Wentworth | ... | Barton / ... (2 episodes, 1966-1971) |
 | Barry Warren | ... | Larry Belmont / ... (2 episodes, 1966-1969) |
 | Bernard Brown | ... | Frank Bowers-Two / ... (2 episodes, 1969-1971) |
 | James Copeland | ... | Oliver MacDonald / ... (2 episodes, 1969-1971) |
 | June Ellis | ... | Brenda / ... (2 episodes, 1969-1971) |
 | Gerald Sim | ... | Det. Sgt. Greene / ... (2 episodes, 1969-1971) |
 | John Berwyn | ... | Japhet / ... (2 episodes, 1969) |
 | Steve Peters | ... | Man / ... (2 episodes, 1969) |