Three young employees of Spofana Company, Zdenek, his girlfriend Vera Novotná and their friend Vera Matousková were rewarded for excellent work by a vacation in the mountain resort of Tatranská Lomnica. The Prague Transport Company controller Gustav Andel (Jaroslav Marvan) also travels to the same destination as a reward. He does not know yet Vera, future wife of his son Mirek, and has decided to secretly check her behaviour in the absence of her fiancée. By mistake he considers Vera Novotná to be his son's girlfriend, and so his investigations cause him plenty of embarrassments.