The Indelicate Balance (1969)

24 years old Harald visits his parents' home in a wintry Sweden with his young wife, Karin after four years. He had left because of the complex relationship with his 40 years old stepmother, Lena. However, the tensions from the past have not yet disappeared and they start spending the days together. So the relationship between Harald and Karin is under pressure. So much so that Karin seeks solace in the arms of another woman, Harald's married half-sister, Ingrid.