Karl Geschwandtner, a porter in a large hotel, has only one wish: one day, he'd like to be the lord and master, as the saying goes: to be the porter and 'ruler' in the hotel. And luck helps him to temporarily fulfill his dream. But Karl doesn't just take over running the hotel, he feels the need to stick his nose in the life of his hotel guests, too. There are couples, who don't want to be put together or apart. When a valuable jewel goes missing, he plays detective and only succeeds in helping the thief to rob the hotel guests at his leisure. Pretty soon, chaos reigns at the hotel; there's massive confusion. Even the newspaper seller, Wally, whom Karl secretly loves, is slowly starting to mistrust him. When the director of "Hotel Europa" finally returns, he throws Karl out, who thereupon simply rents a room as a guest.

Helena's mirror, a valuable piece of jewelry, has been stolen from a museum in Bremen and is to be smuggled across the Alps to the border. Alex Roscher, the border guard, catches the smugglers but gets caught up in a shootout.

The emergency braking of the Orient Express causes chaos. When the lights are switched back on, lawyer Branko is found murdered in his compartment. The Rarna Criminal Investigation Department starts investigating immediately. There are several suspects: Baron Hübner and his divorced wife, the seemingly too staid private detective Holzer and the mysterious Vera Panaid. Suddenly, the mysterious case takes a surprising turn...

A romantic skirmish between an intrusive operetta tenor from the Berlin Theater and a revue diva in Barcelona, who later encounters him, initially unrecognized, as a ballet dancer and, after they marry, plays the role of a housewife to cure him of his arrogance and flightiness. He himself is no stranger to deception, but their joint stage finale is not far off.