A refugee Soviet scientist arrives at a desert airport carrying secret documents, but is attacked by a pair of KGB assassins and escapes into the desert, where he comes in range of an American nuclear test and is transformed into a mindless killing beast.

Tor Johnson
as Joseph Javorsky

Douglas Mellor
as Hank Radcliffe

Barbara Francis
as Lois Radckiffe

Bing Stafford
as Patrolman Jim Archer

Larry Aten
as Patrolman Joe Dobson

Alan Francis
as Mike, also called Art, Radcliffe

Ronald Francis
as Randy Radcliffe

Coleman Francis
as Narrator / Gas Station Attendant / Newspaper Customer

Anthony Cardoza
as KGB Driver / Fat Man in Rescue Plane

John Morrison
as KGB Agent with Mustache