Alan (Terence Hill) is a losing gambler that decides to swindle some mobsters out of a large chunk of change and loses it on a sure bet. He stows away on a small boat captained by Charlie (Bud Spencer) and directs it to an island where he believes there is hidden WWII treasure. Unfortunately, the island is far from deserted... there's natives, slavers and a nutty Japanese soldier who doesn't know that the war is over...