Lonely Hearts

Stefano, a 45-year-old architect, and Giovanna, a young housewife, spend the summer in their quiet house by Lake Como. Their everyday routine feels monotonous and comfortable, shielding them from the outside world. The calm setting foreshadows the disturbances to come.

A young couple pitches a tent on the couple's property and swims naked in the lake. Stefano's initial indignation quickly fades as his interest grows, and he allows them to stay the night. He hints that he would be open to a partner swap, setting the stage for further temptations.

The young couple remains, and Stefano's flirtation with the idea of swapping intensifies. He invites them to spend the night in his house and flirts with the thrill of shared love. Giovanna watches with skepticism as the plan lingers on the edge of their life.

The next morning, the young couple disappears. Stefano's verbal moralism collapses as he immediately seeks sexual fulfillment with his secretary. This marks the beginning of his serial pursuit of unfaithful adventures.

Stefano sleeps with his secretary despite his earlier moral talk. He begins pressing Giovanna about partner swapping again, trying to pull her into the fantasy. Giovanna remains resistant and uninterested in the idea.

Giovanna, while reading the newspaper's box ads, discovers letters that reveal Stefano's scheme to arrange swapping. She confronts him, and he immediately admits his role in the scheme. The revelation turns the couple's evenings into a charged, uneasy game.

The couple spends an evening going through the letters they received, turning it into a shared, amused activity. Stefano's obsession with swapping unsettles Giovanna, yet the idea remains a tense topic between them. The mood swings between humor and underlying tension.

Reluctantly, Giovanna agrees to try swapping, driven more by Stefano's persistence than her own desire. Their first exchange yields an old and unsightly couple, which Giovanna finds ridiculous and dismisses with a laugh. Stefano is disappointed but presses on.

A second couple visits to swap, but tensions surface quickly. Stefano is attracted to the woman's beauty while Giovanna finds the man pushy. Stefano then recalls the woman from a photo as a prostitute, hinting at a possible fraud.

The second couple's visit ends badly as the situation reveals itself as potentially fraudulent. The man promptly makes off with the supposed prostitute, leaving Stefano and Giovanna unsettled and wary of further exchanges. They retreat from the swapping experiment for a time.

After another unsuccessful attempt at a swap, the couple visits a corresponding club in Ticino hoping for a more successful encounter. The visit proves fruitless, reinforcing the limits of their experiment. They ultimately decide to abandon this line of exploration for the moment.

An unexpected opportunity arises when friends Diego and Gabriella show them a large palazzo. Giovanna is captivated by Diego's cultured charm, while Gabriella goes to bed with Stefano in another room. When Diego's piano stops, Stefano frantically searches through bedrooms for Giovanna in a rising sense of crisis.

In the morning, Giovanna appears before Stefano with the face of a woman who has had a great night. He asks her to confirm under oath that nothing happened that night. She confirms, leaving him unsettled and a little alienated as he tries to cope with the new reality.