Lili is a typical girl of our time: she's lonely and tries to convince herself that this is what's good for her. But one day, she finds an old package of letters in her parents' apartment, which her mother apparently didn't want to show her at all. Of course, she doesn't hesitate much, she starts reading, and the past comes alive... an unforgettable summer in the early 1990s, when three good friends are on vacation at Lake Balaton, and of them, only Eszter wants to stay faithful to her boyfriend who left her at home, who swallowed a stake. But her plans, which she usually follows with engineering precision, are slightly messed up when she meets Gergo, easygoing, funny and has another very good quality: he plays in a band and performs with his friends on the beach in Szigliget in the evenings.