An American salvage diver plunges into dangerous intrigue around a sunken treasure in the Philippines.

An airplane carrying a pair of police officers escorting gangsters to prison crash-lands in the African jungle. They are rescued from an attack by savage natives by a white woman who appears out of nowhere, and it turns out she is a lost heiress who herself crash-landed in the jungle years before.

Captain Ralls fights Dutch shipping magnate Mayrant Sidneye for the woman he loves, Angelique Desaix, and for a fortune in gold aboard the Red Witch.