A married couple is vacationing at Lake Wörthersee. Two female friends discover the husband's clothes and camera on the shore. Since they are currently disillusioned with men in general, they decide to play a little prank: one friend takes a photo of the other in a provocative pose. However, when the wife discovers the photo, she becomes convinced her husband is cheating on her. When he subsequently runs into the girl from the photo by chance, the wife repeatedly engineers encounters between the two, hoping to catch them in the act. A kiss does indeed occur, and the husband has his work cut out for him trying to convince his wife that it was all just a harmless joke.