Based on the classical novel "Treasure of Silver Lake" by Karl May. Cowboys Hobble Frank and Tante Droll are instructed to deliver the legacy of chief Weiser Bär, a map to the legendary Treasure of the Silver Lake, to his hiers Großer Bär and Kleiner Bär. But the bandit Cornel Brinkley and his buddies manage to steal the map and so Frank and Droll call up Old Shatterhand and Winnetou, to help them in their quest to recapture the map and save the treasure.