Sylvia Anderson as Lady Penelope Creighton-Ward (voice)

Ray Barrett as John Tracy / The Hood (voice)

Alexander Davion as Space Captain Greg Martin (voice)

Peter Dyneley as Jeff Tracy (voice)

Christine Finn as Tin-Tin Kyrano (voice)

David Graham as Gordon Tracy / Brains / Aloysius Parker (voice)

Paul Maxwell as Captain Paul Travers (voice)

Neil McCallum as Dr. Ray Pierce (voice)

Bob Monkhouse as Space Navigator Brad Newman / Swinging Star Compere (voice)

Shane Rimmer as Scott Tracy (voice)

Charles Tingwell as Dr. Tony Grant / Angry Young Man / Public Relations Officer (voice)

Jeremy Wilkin as Virgil Tracy / Space Exploration Center President (voice)

Matt Zimmerman as Alan Tracy / Messenger (voice)

F. Vivian Dunn as Himself (voice)

Cliff Richard as Cliff Richard Jr. (voice)