Flash, Dale and Dr. Zarkov travel 1500 miles beneath the Earth's surface to confront the ruler of a subterranean people who are intent on destroying those who live above ground.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.