Unsettled by his recent divorce, Andreas Winkelman (Max von Sydow) lives on a remote Swedish island. When he meets the unhappy married couple Elis and Eva Vergerus (Erland Josephson, Bibi Andersson), Andreas begins a brief affair with Eva, which leads to a romantic involvement with their friend Anna Fromm (Liv Ullmann), who is grieving the loss of her family. As these relationships unfold, someone on the island is killing animals, lending the drama a mysterious backdrop.