Henrik Durvard has taken over the country of Lombuanada by military coup, and holds the natives in terror. He has obtained a diamond from the native miners, and the IMF are assigned to take it away from him.

A former prison guard, Sefra, has acquired a supply of cesium 138, which explodes at temperatures above 70 degrees. Rollin and Barney go in as a photographer and model respectively, and Sefra "learns" that Barney is a former prisoner returning for revenge.