American International Pictures and Amicus join forces to bring you one of Edgar Rice Burrogh's non-Tarzan stories to the screen. LAND THAT TIME FORGOT. Starring Doug McLure about a Submarine in WWI going into an unknown land where prehistoric life-forms live. Cheesy special effects. If JAWS scares you, then this one is highly recommended. Followed by PEOPLE THAT TIME FORGOT (1977).
This trailer is in widescreen, but cut off at the end.