Happy End am Wolfgangsee (1966)

The Hotel Excelsior in an idyllic Austrian lakeside situation is the base for some misunderstandings. There's a resident band, and Bibi Werner is impersonating his brother who was booked as the drummer, but broke his arm just before the season started. The rest of the band aren't fooled for a minute and their red blooded instincts take over. Meanwhile the hotel owner, playboy James, has called in a tax adviser to help with the hotel finances and another romantic interest develops. And Pankraz, the hotel porter, has been reading too many James Bond books and sees espionage at every turn, and decides to intervene personally.