Germany, the summer of 1976: Eva, her husband Bernd and their children drive to the summer cottage of Grandmother Sophie. It's a long-standing tradition that all branches of the family meet there every year to spend the holidays together. Yet this year everything is different: Sophie recently passed away, and a lightning bolt has destroyed the old tree in the garden. While the children are having carefree fun, the adults get increasingly tense. Eva feels annoyed by her sister-in-law Gitti, and Bernd tries to set the record straight with his father Erich. Aunt Ilse flirts with the female neighbor, and freethinking aunt Mathilde turns the garden into a nude area. Meanwhile, the kids explore the surroundings and the mysterious estate next door. When a girl from the area disappears, the dramatic news threatens to shatter the illusion of an idyllic family reunion.