In this low budget fantasy adventure from Britain, based on Edgar Rice Burroughs' 1918 science fiction novel, a German submarine holding American prisoners of war during World War I, veers off course. Lost at sea, the submarine empties its fuel supply and runs aground on an uncharted island in the Antarctic. The survivors find that the island contains an ancient oil refinery that can be used to fuel the submarine. The only problem is that the group of Germans and Americans have to battle gigantic dinosaurs and primitive cavemen as they make their way through the island. The Land That Time Forgot was enough of a success to spawn a 1976 sequel called The People That Time Forgot.
by Paul Brenner synopsis