French military man Adrien Dufourquet (Jean-Paul Belmondo) gets an eight-day furlough to visit his fiancée, Agnes (Françoise Dorléac). But when he arrives in Paris, he learns that her late father's partner, museum curator Professor Catalan (Jean Servais), has just been kidnapped by a group of Amazon tribesmen who have also stolen a priceless statue from the museum. Adrien and Agnes pursue the kidnappers to Brazil, where they learn that the statue is the key to a hidden Amazon treasure.