Rebellious Ossi enjoys drinking, smoking and playing cards. Doctor Kersten is hired to teach the young girl more ladylike manners, but Ossi challenges him by changing her role: She disguises herself as a gentlemen, and subsequently visits a nightclub. There she meets the unknowing Kersten, with whom she spends the evening chasing girls and drinking heavily. Both ‘men’ feel attracted to each other, which finally leads to a fateful kiss between them. The next morning, Ossi and Kersten wake up in each other’s bed. After Ossi reveals her true identity, she and Kersten embrace.