Four kids - Eugen, Wrigley, Bäschteli and Eduard - leave for an adventure around Switzerland, searching for the fabulous treasure of Titicaca Lake, discovered by Fritzli Bühler.
They live behind the rails of the classification yard in a small and shabby hut. They take the days as they come, refuse to work on principle and pinch together their livelihood. The three tramps Dürst, Barbarossa and Clown are content with what they have and ignore the outside world, and so far they have fared well. Until now...