The Land Unknown

Four members of a major Antarctic expedition - including Navy Cmdr. Hal Roberts and reporter Maggie Hathaway - find themselves stranded in a remote - and prehistoric - area when their helicopter is forced to land inside a volcanic crater some 3,000 feet below sea level. They have to deal not only with the oppressive heat but also with prehistoric creature a various sorts. Another danger is a human: Dr. Carl Hunter, who has been stranded there for over 10 years. If they are to survive, they will need to repair the helicopter. Hunter may have a supply of spare parts but the price he demands may be too high.