Director Michelangelo Antonioni had originally intended to use Terence Stamp in the title role before settling on David Hemmings. The film was noted for it's numerous cameos including The Yardbirds, Jane Birkin, Veruschka and an uncredited Peggy Moffitt. It also featured performances from popular actresses Vanessa Redgrave and Sarah Miles and featured a score by jazz musician Herbie Hancock. The film was such a success, despite what was considered sexually explicit scenes by the standard of the day, that it contributed to the eventual collapse of the production code.
Today Blow-Up is best known for it's sexual nature, particularly the infamous scene with Jane Birkin (although by today's standards it's relatively harmless). The film however is also a fascinating look at Swinging London, and blurs the lines between surrealism and understated naturalism. There are two worlds in Blow-Up, the glamorous world of models and clothes seen through Thomas' camera, and the seedy underbelly that Thomas both lives and works in. It's interesting that despite his lucrative job as a fashion photographer Thomas is most excited about a book he is working on that displays the lives of everyday Londoners.
The start and end of the film are bookended by the appearance of a group of mime artists. They seem to reflect the quality of illusion in Thomas' own life as well as the false world of the models, how they appear before the camera isn't necessarily how they are in real life. The eerie quality of the film is heightened when the mime artists are playing an imaginary game of tennis, but when the camera focuses on Thomas, we can hear a real ball being hit. Is it an amusing touch? Or does it force us, as an audience, to question Thomas's memories of the murder. Did it happen at all? Is the world we see throughout the film the real world?
The cinematography is stunning, using light and darkness to highlight the characters emotions. Characters are frequently seen with their backs towards the camera, their expressions and emotions obscured from view. Thomas' camera is an intrusion into lives, and yet it also cannot reveal enough. The world in Blow-Up is torn between an intense openness and a secretive privacy, two oppositions displayed by both Thomas and Vanessa Redgrave's character, Jane.
The final shot highlights Thomas' alienation, his inability to make a meaningful connection with anyone and his confusion with the world he lives in.