The Land Unknown (1957)

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.
Virgil W. Vogel, Joseph E. Kenney
Jock Mahoney, Shirley Patterson, William Reynolds, Henry Brandon, Douglas Kennedy, Phil Harvey, Kenner G. Kemp, Bing Russell, Bert Stevens
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