Vicki Allessio, Glenda Jackson, a divorced British mother of two, meets Steve Blackburn, George Segal, an American married man, in a taxi in London. Steve is drawn to Vicki and invites her to tea, then lunch, and finally suggests they explore sex together. Vicki agrees but makes it clear she wants something light, uncomplicated, and in a sunny setting. Steve arranges a getaway to Málaga, Spain, hoping for a discreet escape from their respective realities.
Their plans are thrown off when Steve’s wife, Gloria Blackburn, Hildegard Neil, suddenly appears. To keep their affair secret, Steve pretends that Vicki is his mother. He cancels the plane tickets he’d organized for his family and runs into Walter Menkes, a movie producer, at the airport. Steve, unable to admit his relationship with Vicki, ends up sitting next to Walter on the flight while Vicki sits apart.
In Málaga, Steve gives Walter the last decent rental car to get him out of the way, but the handover backfires as Walter remains determined to join the trip. The car Walter ends up driving is Italian and has a clunky clutch, which makes the ride uncomfortable for Vicki. The pair struggle up several flights of stairs to reach their hotel room, setting a tense tone for what follows.
Their first night together is awkward as they clash over their sexual preferences. Steve injures his back, needing medical attention and an early night. The next morning, Vicki encounters an American woman named Patty, K Callan, but declines her invitation to dinner. Steve wakes to find Vicki sunbathing on the balcony, and the couple finally have sex.
Afterwards, Steve is disappointed by Vicki’s lack of evident enthusiasm, fueling friction between them. During a round of golf, Vicki takes offense at Steve’s competitive behavior against a local boy. The mood stays charged as Vicki decides to have dinner with Patty while Steve arranges a dinner with Walter. To their surprise, Patty turns out to be Walter’s wife, making the dinner with the four of them deeply awkward.
An argument in their hotel room leads Steve and Vicki to abandon the Málaga plan and return to London. At the airport, they discover that the last two plane tickets have already been sold, forcing them back to the hotel with a mix of frustration and humor. The pair’s chemistry begins to show through as they acknowledge a growing connection.
Walter and Patty notice the developing bond between Steve and Vicki. Walter shares his own holiday romance experience and warns Steve that such affairs rarely end well. Despite the warning, Steve expresses a desire to continue seeing Vicki when they return to London. They secretly rent a flat, keeping their affair out of sight from their respective circles.
As their relationship deepens, it becomes more complicated. Vicki invests effort to make things work, but Steve often leaves her feeling let down. He dashes off after sex without noticing that Vicki has prepared a lavish meal for him. She also seeks companionship with a gay coworker, who’s unavailable, adding to the sense of loneliness. Steve later brings flowers to apologize, only to walk away without a word.
Tensions rise as Steve’s coworkers start noticing something off. He tries to meet Vicki in the evening but forgets he has obligations with his wife. When Gloria calls, Steve can’t reach Vicki, and Vicki spots Steve with Gloria at the theater. She feels betrayed and confronts him when he finally arrives at their flat.
The next morning, Steve sends a telegram to end their relationship but quickly changes his mind and rushes to the flat; by then, Vicki has already read the telegram and begins packing. When Steve arrives, he finds Vicki at a bus stop. Despite his efforts to catch her attention, she takes a taxi with another man who asks if he is married, and she walks away, leaving the taxi behind.
In the end, Vicki moves forward, choosing a new direction in her life and leaving the affair behind.
