Planet Earth is a devastated wasteland, and what's left of humanity has colonized the Moon in domed cities. Humanity's continued survival depends on an anti-radiation drug only available on planet Delta Three, which has been taken over by Omus, a brilliant but mad mechanic who places no value on human life. Omus wants to come to the Moon to rule and intends to attack it by ramming robot-controlled spaceships into the domes. Dr. John Caball, his son Jason, Jason's friend, Kim, and a robot named Sparks embark on Caball's space battlecruiser on an unauthorized mission to Delta Three to stop Omus.
Jack Palance
as Omus
Carol Lynley
as Nikki
Barry Morse
as Dr. John Caball
John Ireland
as Senator Smedley
Nicholas Campbell
as Jason Caball
Anne-Marie Martin
as Kim Smedley
Greg Swanson
as Sparks (voice)
Mark Parr
as Sparks
William Hutt
as Lomax (voice)
Ardon Bess
as Merrick
Lynda Mason Green
as Lunar technician
Albert Humphries
as Robot technician
