Baron Conrad Crusenhielm is hit in the head during a drunken brawl. Suffering from amnesia, he is mistaken for the lost sailor Karlsson and taken to the navy vessel Fylgia.
Celestin is the singing teacher in a monastery and Denis is one of her students. They both dream about the life outside. (It's a Swedish version of the famous vaudeville-opérette "Mam'zelle Nitouche").
