John Alkin (Frank)
Spencer Banks (Simon Randall)
John Barron (Devereaux)
Derek Benfield (Frank)
Cheryl Burfield (Liz)
Ian Fairbairn (Alpha 4 / Dr Frazer)
Peter Fairley
David Graham (Controller 2957)
Mary Preston (Beth)
Denis Quilley (Charles Traynor)
Iris Russell (Jean)
Peggy Thorpe-Bates (Dr Joynton)
