The narrative covers a day in the life of a glamorous fashion photographer, Thomas (Hemmings), the character’s creation being inspired by the life of an actual “Swinging London” photographer, David Bailey, and contemporaries such as Terence Donovan, David Montgomery and John Cowan.
After spending the night at a doss house, where he has taken pictures for a book of art photos, Thomas is late for a photo shoot with Veruschka at his studio, which in turn makes him late for a shoot with other models later in the morning. He grows bored and walks off, leaving the models and production staff in the lurch. As he leaves the studio, two teenaged girls who are aspiring models (Birkin and Hills) ask to speak with him, but the photographer drives off to look at an antique shop.
Wandering into Maryon Park, he takes photos of two lovers. The woman (Vanessa Redgrave) is furious at being photographed, pursues Thomas, demands his film, and ultimately tries to snatch his camera. He refuses and photographs her as she runs off.
Thomas then meets his agent Ron (Peter Bowles) for lunch, and notices a man following him and looking into his car. Back at his studio, the woman from the park arrives, asking desperately for the film. They have a conversation and flirt, but he deliberately hands her a different film roll. She, in turn, writes down a false telephone number and gives it to him.
He, curious, makes many enlargements of the black-and-white film of the two lovers. They reveal the woman worriedly looking at a third person lurking in the trees with a pistol. Thomas excitedly calls Ron, claiming his impromptu photo session may have saved a man’s life. Thomas is disturbed by a knock on the door, and it is the two girls again, with whom he has a romp in his studio and falls asleep. Awakening, he finds they hope he will photograph them, but he realizes there may be more to the photographs in the park. He tells them to leave, saying, “Tomorrow! Tomorrow!”
Further examination of a blurred figure under a bush makes Thomas suspect the man in the park may have been murdered after all, during the time Thomas was arguing with the woman around the bend.
As evening falls, the photographer goes back to the park and finds the body of the man, but he has not brought his camera and is scared off by the sound of a twig breaking, as if being stepped on. Thomas returns to find his studio ransacked. All the negatives and prints are gone except for one very grainy blowup of what is possibly the body.
After driving into town, he sees the woman and follows her into a club where The Yardbirds, featuring both Jimmy Page and Jeff Beck on guitar and Keith Relf on vocals, are seen performing the song “Stroll On”. A buzz in Beck’s amplifier angers him so much, he smashes his guitar on stage, then throws its neck into the crowd. A riot ensues. The photographer grabs the neck and runs out of the club before anyone can snatch it from him. Then, he has second thoughts about it, throws it on the pavement, and walks away. A passer-by picks up the neck and throws it back down, not realizing it is from Beck’s guitar. Thomas never locates the elusive woman.
At a drug-drenched party in a house on the Thames near central London, the photographer finds Veruschka, who had told him that she was going to Paris; when confronted, she says she is in Paris. Thomas asks Ron to come to the park as a witness, but cannot convince him of what has happened because Ron is incredibly stoned. Instead, Thomas joins the party and wakes up in the house at sunrise. He returns to the park alone, only to find that the body is gone.
Befuddled, Thomas watches a mimed tennis match, is drawn into it, and picks up the imaginary ball and throws it back to the two players. While he watches the mime, the sound of the ball being played is heard and his image fades away, leaving only the grass as the film ends.