So, what’s the deal? To mark their centennial production, Hammer Films revived One Million B.C., originally released in 1940 and not exactly a critical darling. The new version ended up being quite popular at the box office, while also establishing Raquel Welch as a well-known figure and boosting Ray Harryhausen’s reputation considerably. The storyline is pretty simple. There are two groups living during prehistoric times: the Rock People and the Shell People. The Rocks are more rough around the edges, while the Shells seem to have things a bit more together. Tumak (played by John Richardson) of the Rocks and Loana (Welch) find themselves thrown together, dealing with biases and plenty of enormous creatures! Wonderful! That’s essentially it; the point is obvious, but really we're here for the dinosaurs and giant animals (and alright, the scantily dressed cave people too), as Harryhausen once again demonstrates why he was so respected in animation. There are some decent fight scenes, a little bit of eye candy, and an explosive volcanic ending—it’s all pretty enjoyable overall. Naturally, this isn't meant to be educational; after all, as Harryhausen often said, they weren’t making something for academics! 7/10

Source on TMDB