In turn of the century Mexico, a carnival stuntman (James Franciscus), a paleontologist (Laurence Naismith), a cowgirl (Gila Golan) and her manager (Richard Carlson) stumble across a hidden valley where long thought extinct creatures still survive. When they see a Tyrannosaurus, their first thought is to capture it and turn it into a sideshow at their traveling rodeo. Directed by Jim O'Connolly, this lacks the magic of the previous Ray Harryhausen/Charles H. Schneer collaborations like 7TH VOYAGE OF SINBAD and JASON AND THE ARGONAUTS because the lack of mythological fantasy elements. However, it's a still an entertaining action film elevated by Harryhausen's superior creature effects. In films like this, where the creature is kidnapped by humans, I have no sympathy for the humans when the creature turns and gobbles them up. The film has a fiery finale but I felt sorry for the creature rather than satisfaction that he had been destroyed. The characters are a greedy and annoying lot anyway. There's a thrilling underscore by Jerome Moross (THE BIG COUNTRY). With Gustavo Rojo and Freda Jackson.