The story happens between 29 June and 29 July, presumably in 1970. (Inter-title cards of the dates are displayed before the daily events are shown.)
While holidaying at Lake Annecy on the eve of his wedding, career diplomat Jérôme accidentally meets up with Aurora, an old personal friend. Through Aurora, he meets Aurora's landlady, Madame Walter, and Laura, Madame Walter's youngest teenage daughter. Observant Aurora detects Laura's crush on Jérôme, and advises Jérôme of such. After Jérôme and Laura take a hike in the mountains together, she confesses that she is "a little in love with" Jérôme.
Days later (on 8 July), Laura's attractive older half-sister Claire arrives. Upon seeing Claire's knee on a ladder, he finds himself longing to touch her knee. However, Jérôme controls his temptation. Eventually an opportunity presents itself during a boat trip on the lake when Jérôme and Claire have to seek shelter in a hut from an approaching storm. Jérôme tells Claire that he saw her boyfriend, Gilles, together with another girl. When Claire starts to cry Jérôme consoles her by placing his hand upon Claire's knee.
Jean-Claude Brialy as Jérôme Montcharvin, the diplomat
Aurora Cornu as Aurora, the novelist
Béatrice Romand as Laura, the younger half-sister
Laurence de Monaghan as Claire, the elder half-sister
Michèle Montel as Madame Walter, mother to Laura and Claire
Gérard Falconetti as Gilles
Fabrice Luchini as Vincent
The film received the Louis Delluc Prize for Best French film of the year, the 1971 Prix Méliès and the Grand Prix at the San Sebastián International Film Festival. It was named Best Film by the National Society of Film Critics and Best Foreign Film by the National Board of Review. It was nominated for Best Foreign Language Film at the Golden Globe Awards.
It was a huge international success. Vincent Canby called it "something close to a perfect film." Cecile Mury of Télérama said "This camera outdoors gives the appearance of a small story where it goes 'nothing.' Yet these 'fragments of a love speech' make up a special study of desire, verbal pleasure, almost literary, which accompanies every inclination. A jewel."
It was Rohmer's second film shot in color, with Rohmer explaining "the presence of the lake and the mountains is stronger in color than in black and white. It is a film I couldn't imagine in black and white. The color green seems to me essential in that film...This film would have no value to me in black and white."