After witnessing the destruction of five planets, Dr. Zarkov determines that the explosions were created by a nuclear bomb fueled by a material that takes hundreds of years to explode. Dale, Flash and the doctor journey back to 1950s Berlin to locate such a bomb planted on Earth. br br Directed by Gunther von Fritschbr Starring Steve Holland, Irene Champlin, Joseph Nashbr br Castbr Steve Holland as Flash Gordonbr Irene Champlin as Dale Ardenbr Joseph Nash as Dr. Hans Zarkovbr Henry Beckman as Cmdr.