In the Belgian Congo of 1907, Hayward is a missionary nurse who sets out to minister to the feared Bakuba tribe. She hires guides Slezak and Mitchum to take her into the interior, but their motives are somewhat less altruistic than hers. They have heard stories of gold in Bakuba territory
and plan to use Hayward's mission to learn of its whereabouts. As they travel through the jungle, Hayward stops to cure the wife of a native chief. This infuriates the local witch doctor, and he puts a tarantula in Hayward's bed in vengeance, but she manages to escape its venom. Traveling on,
Mitchum saves a boy from a lion, and the child turns out to be the son of the Bakuba chie...