In prehistoric times, young caveman Tumak (Victor Mature) was banished by his people for defying the authority of his chieftain father (Lon Chaney, Jr.). Fending for himself, he wins the heart of rival tribe princess Loana (Carole Landis), and together they may rescue both their clans from ravenous dinosaurs and the unforgiving elements. Long-demanded action-fantasy from Hal Roach, complete with it's memorable, often-cribbed special effects sequences, also stars Conrad Nagel, John Hubbard, Mamo Clark.