Two musicians, Hans and Peter, are out of work. They make regular visits to the booking agent, but there's no work. After several false starts, they are desperate, and when they hear that an all-woman band, the Alpine Violets, have been let down and are desperate for two female musicians, they know that fate is knocking for them. When they hear that the band is going to a luxury Alpine hotel to record a gramophone record, they can't wait to get on board. They enlist the help of a friendly makeup artiste and practise their girly body language. After a street test they are sure they pass, so it's back to the agency to volunteer. They pass a quick audition, so it's down to the station for the night train to Ingolstadt, with the rest of the band. They get introduced to all the other girls, who are already in their pyjamas in their sleeping berths. After a lot of giggling and innuendo, fortunately they are in their own compartment for the night. Next morning, the train hasn't yet reached the destination, and Hans goes to the breakfast car in his male clothes. A romantic interest develops with one of the real girl musicians, Gabi. Peter wants some of the action too, so at the hotel he dresses in his male clothes, and pretends he has just arrived, and another romantic interest develops, with Lydia, another of the musicians. After a rehearsal, the whole band are free for the evening, and Peter and Hans go to a night club in the town, in their male clothes, and pursue the romantic interest with Gabi and Lydia, with some competitive horseplay between the two men. Gabi increasingly grows suspicious about the siimilarity between Peter and Hansi (his female persona), and Peter decides not to show up in role for the actual recording. With time pressing, and Hansi apparently disappeared, the lady bandleader is desperate. Peter is hanging around, in his male clothes, and he has revealed that he plays the piano, and so in desperation he is eventually persuaded to be dressed up by the girls in Hansi's clothes, so that the bandleader won't sack her. Gabi by this time knows exactly what is going on. Peter now appears, dressed as a woman and the record company manager recognises him as Hansi. He demands demands to know what she is playing it, first being sick, and not answering the phone and so on. If Peter tells the truth, no-one will know who else is not really what they seem ...