Navy Commander Alan Roberts is assigned to lead an expedition to Little America in Antarctica to investigate reports of a mysterious warm water inland lake discovered a decade earlier. His helicopter and its small party, including reporter Maggie Hathaway, is forced down into a volcanic crater by a fierce storm. They find themselves trapped in a lush tropical environment that has survived from prehistoric times.
Jock Mahoney
Commander Harold 'Alan' Roberts
Shirley Patterson
Margaret 'Maggie' Hathaway
William Reynolds
Lt. Jack Carmen
Henry Brandon
Dr. Carl Hunter
Douglas Kennedy
Capt. Burnham
Phil Harvey
Machinist's Mate Steve Miller
Kenner G. Kemp
Officer at Briefing / Officer on Ship (uncredited)
Bing Russell
Radio Operator (uncredited)
