When Dinosaurs Ruled the Earth is a movie starring Victoria Vetri, set in the time of cavemen. The film was made by Britain's Hammer Films. Like several of Hammer's previous films, such as One Million Years B.C. (1966), the film portrays dinosaurs and humans alongside each other. Directed and scripted by Val Guest, it was based on a treatment by J.G. Ballard, and nominated for an Oscar for its visual effects.