Naughty in the Summer

11-year-old Jonas lives in Germany with his mother and younger brother. Because of a quarrel with his mother, Jonas made an excuse and boarded a train alone to visit his grandfather in Slovakia. He was originally looking forward to spending the summer with his grandfather Bernard, but found that his life had changed since his grandfather retired. For Jonas, how to return his grandfather to a normal life and reconcile with his mother is a double challenge. Like all children, Jonas grew up unknowingly during this summer vacation.