Travelers heading west in a wagon train, under repeated assault by Indians, discover someone in their group is supplying rifles to their attackers.

Prince Ali wants the Golden Idol of Watusi and hires a ruthless hunter to get it for him. Bomba has the idol and, with the help of Commissioner Barnes, Eli, and a beautiful archeologist, he foils Ali's plans.

Julie, an American on vacation in Mexico, spots a giant, one-eyed amoeba rising from the ocean, but when she tries to tell the authorities, no one believes her. She finally teams up with a marine biologist in an attempt to destroy it.