This movie is considered a pictorial radical film. Both Ingmar Bergman and his cinematographer Sven Nykvist felt that mid-shots were boring; therefore, the film consists of a few wide shots, occasional mid-shots, and many, long and intense closeups.
In the spring of 1965, Ingmar Bergman was admitted to the Sophia Hospital in Stockholm for double pneumonia and acute penicillin poisoning. While hospitalized, he created the basic script of this movie. Inspired by August Strindberg's one-act play "The Stronger", an existence which consisted of dead people, brick walls, and some dreary park trees and conceived as a sonata for two instruments.
Although the age of boys Alma and her friend have sex with on the beach is never stated, the script specifies their ages as 13 and 16.