Masten Thrust (Richard Boone), a billionaire oil tycoon and big-game hunter, has announced the discovery of a lost world hidden inside the warm pocket of a dormant volcano at the North Pole. Upon arriving, Thrust and his team find that the hidden world is populated with both dinosaurs and prehistoric humans. While the humans give the explorers a fair bit of trouble, the real danger is the hungry tyrannosaur intent on hunting down the Great White Hunter and his crew. Also stars Joan Van Ark and Steven Keats.
This film comes from an uncut widescreen Japanese import print, which includes 14 minutes of footage, not seen in the US version.
Richard Boone continued working until the end of the 1970's and died from throat cancer on January 10th, 1981. His ashes were then scattered in the ocean off of Hawaii. He was 63.
At the end of his career, Steven Keats was playing the part of Ed McClain on the soap opera Another World. Unexpectedly, on May 8th, 1994, Keats was found dead in his apartment in Manhattan. His death was ruled a suicide. As for the reason he took his own life, it has remained a mystery. He was 49.