Watch One Summer of Happiness for Free: How to Stream the Movie Online at 123Movies. . The young high school graduate Göran and the 17-year-old Kerstin get to know each other on the estate of Göran's uncle Persson and fall in love. But their relationship is watched suspiciously by the jammed adult world. While Persson has an understanding of the youth, Kerstin's parents and the pastor of the village rant against the alleged immorality of the young people. Despite all the malice, Göran and Kerstin decide for their love. But this love should last only one summer.