Bud Abbott and Lou Costello are back, and this time on the trail of a hidden diamond mine located in the deepest, darkest jungles of Africa. Lou plays Stanley Livington, a wimpy book salesman, who at the urging of his friend Buzz Johnson (a big game hunter played by Bud) agrees to lead an African expedition, despite his fear of wild animals. Along the way they bump into a giant gorilla, a cannibal tribe and villainous expedition members whose real motives imperil duo with hilarious results.