Bernhard "Big Mäc" Maurer, an ex-motorcycle freak and bored piano teacher, is voted the "perfect motorcyclist" by the trade magazine Motorrad after quitting his job as a music teacher at a Munich high school. He is promised a bonus of $50,000 if he manages to beat a Japanese team in an adventure rally from the Zugspitze to Kilimanjaro. Maurer agrees and chooses as his second man, the technician, his young neighbor Max. Max, for whom an apprenticeship is at stake, injures himself shortly before the start of the rally and has to sit out. Without Maurer's knowledge, Max's almost identical-looking sister Maxi takes over the role of the boy..