Premier fantasist Ray Harryhausen’s special visual effects—dinosaurs, a giant turtle—and Raquel Welch’s captivating presence helped Hammer hit the box-office jackpot with Disney veteran Chaffey’s adventure, a remake—if not update—of the 1940 movie. Each prehistoric tribe is unhappy in its own way, and Welch’s migration from one to another both soothes and inflames tensions. With John Richardson and Martine Beswick, who were soon married in real life.