A desensitized-to-life, nihilistic, high-fashion photographer Thomas (David Hemmings) in London, who lives a mid-60s life of excess (riches, fame, and women), becomes bored with his lucrative career of glamour photography. So he resorts to photographing, in documentary style, the seamy and sordid side of life in London, in flophouses and slums.
Innocently, he takes candid photos in a deserted park of a lover’s tryst-rendezvous between a kerchief-wearing woman (Vanessa Redgrave) and a middle-aged, gray-haired man in a light-gray suit. She pursues him to ask for the illicit photos, as he imagines that he has witnessed a scene of sexual intrigue – never thinking that he may have accidentally obtained visual, criminal evidence of a murder.
– the photographer’s erotic, photo-shoot crawl – to the point of orgasmic release and satisfaction – over the supine body of model Verushka, while he snaps fashion photos.
– the woman from the park’s visit to his studio, to again desperately and persistently beg for the undeveloped roll of film by becoming topless. He becomes both intrigued and suspicious. To get her to leave, he gives her a different roll of undeveloped film.
– the suspenseful, obsessive sequence of the photographer processing and blowing up several pictures from his park visit, and magnifying them larger and larger to poster size. As tension heightens, he pins the pictures on the wall of his living room – in sequence – giving them life as if they were individual frames in a motion picture. Ultimately, they reveal a riveting possibility – a man and a gun in the shadows of some bushes behind a fence. He speculates that he foiled a potential murder – but further blow-ups reveal what could be a dead body.
– a very sexual, menage a trois romp with two wanna-be teenage models (blonde Jane Birkin and brunette Gillian Hills), who wrestle with him on a large roll of purplish-blue backdrop paper, with quick glimpses of female pubic hair after they have been stripped of their clothes.
– his voyeuristic viewing of his unhappily-married friend Patricia (Sarah Miles) making love to her husband – his presence arouses the passion of the woman.
– Thomas’ return to the park to find the corpse next to some bushes, but before the following morning, the corpse has disappeared and his photographs are stolen. The evidence gets at once more difficult to ignore and more impossible to define. Without photographic evidence produced by his camera-tool – his sole means of communicating with the world, he is left with nothing.
Another indelible image emphasizing the slim line between objective reality and illusion – in the film’s finale, he participates with a group of pantomiming students in white-face, tossing an invisible tennis ball to them as they play an invisible game of tennis with non-existent rackets and balls, and an audience. On the soundtrack, one can hear the illusion in Thomas’ mind – the sound of an actual tennis game. The film ends with an aerial view of Thomas standing in the middle of a grassy field in the park near the tennis court, with his camera in his hand. (Copy of http://www.filmsite.org/blow.html)