Trying to win the Three C's railroad line for his home town of Topaz, Colorado, Nicholas "Nick" Tarvin journeys to India to secure the famed jewel known as the Naulahka, which he plans to present to Mrs. Mutrie, the railroad president's wife. Nick's fiancée, Kate Sheriff, having graduated from medical school, also goes to India, but her aim is to provide the Indians with modern medical care. The Naulahka is possessed by the Maharajah, whose second wife, a dancer named Sitahbai, hopes to have her son, rather than the real prince, named as the heir to the Maharajah's throne. Sitahbai plans to kill the young prince, the son of the Maharajah's first wife, but Nick repeatedly saves him. After Sitahbai's plot to kill Nick fails, Nick threatens to hold the dancer captive until daybreak unless she gives him the Naulahka. Sitahbai reluctantly consents, but Kate, knowing that the loss of the jewel will mean Sitahbai's death, convinces Nick to return it to her. Kate and Nick return to Colorado without the Naulahka to find that the railroad tracks have already been laid through Topaz.