Peter Dyneley

Jeff Tracy (voice)

Shane Rimmer

Scott Tracy (voice)

Jeremy Wilkin

Virgil Tracy / Power / DJ Tom (voice)

Matt Zimmerman

Alan Tracy (voice)

David Graham

John Tracy / Brains / Loman / Sentinel Base Computer (voice)

Ray Barrett

Rick O'Shea (voice)

Sylvia Anderson

Professor Mitchell (voice)

Christine Finn

Tin-Tin Kyrano / Grandma Tracy (voice)

Charles Tingwell

International Space Control (voice) (uncredited)