A group of jolly young people work in the Prague Tesla factory, also spending most of their leisure time together. One of them, guitar player Zdenek, begins to shun his friends' company. He has fallen in love with Vera, who does not belong to the group. The happy-go-lucky young man already has several acquaintances and has his own method to get a girl: to take his motorcycle, his guitar and a bottle of wine and take her to a rented houseboat. Vera, however, is different and gets angry at Zdenek. But she is fond of him and thus eventually spends a whole evening with him on the houseboat. At a preventative medical examination, the doctor tells Vera she is pregnant.