Sailors Jochen, Carlo, and Blacky sign on to an old steamboat. It's a good thing Blacky oversleeps the ship's departure. This allows him to track down a gang of criminals. Their boss is planning an insurance fraud and wants to blow up the ship and its crew.

With rumbling stomachs and no engagement, musicians Pit, Max, Bill, Gus, Eddi, and Giorgio are on their way to visit their Uncle Hermann, who runs a sports school on Lake Wörthersee. Along the way, they meet the charming teenagers Susi, Evi, Sieglinde, Inez, and Francis, who are on their way to a girls' boarding school. A strict boarding school where male visits are, of course, frowned upon. So the musicians dress up in drag and visit their friends disguised as 'aunts and cousins.' And, as expected, things soon go haywire.

Albert and Corinna begin a camping site in their backyard and soon welcome a bunch of eccentric, love lost holiday goers.

At the behest of their boss, London private detective Charly Biff and his assistant Ingrid are supposed to relax on a cruise along the Adriatic coast. Even before the ship sets sail, Charly gets on the trail of drug smugglers in the port of Portoroz. He soon finds out that they want to transport "snow" on the vacation steamer to Italy and sell it there. And while the other passengers enjoy themselves - and some even discover love - Charly follows the crooks' trail.

Because factory owner's son and womanizer Karl Fischer is constantly avoiding his rich fiancée Almut, his father Waldemar sends the flighty little boy to Italy, where he is supposed to work in his future father-in-law's business and come to his senses. The business is a beach hotel where Karl, booked by the drunken janitor as "Carla", ends up in a triple room where two girls are billeted. Karl finds the woman of his life in the beautiful black-haired Karin.