Freda Jackson

Vivianne is a young woman ostracised when her boyfriend is arrested for murder, and is forced to rent a room in a decrepit boarding house for unmarried mothers ran by "Nellie" Alistair, a ruthless woman with sinister motives, who takes pleasure exploiting her vulnerable tenants.

The discovery of a midget horse, thought to be of a species fifty million years old, prompts members of a Wild West show to venture into Mexico's Forbidden Valley in search of world-wide fame and untold wealth. But they are met by prehistoric monsters, including "Gwangi," a giant dinosaur that decimates their ranks.