Thomas (David Hemmings) is an artist who has lost interest in his work. While he is still able to appreciate other's work, and frequently visits antiques shops, he never has the patience to appreciate his own - resulting in the mis-treatment of many of his models.
On a whim, he decides to visit a local park where he spots a young couple and decides to photograph them. When the lady spots him she requests the photos and tries to snatch them. Later, he develops the photos, and upon seeing some odd expressions he blows them up to reveal a gun and a body.
During the 1960's, although sex was becoming more prominent and open talked about in day-to-day life, film had yet to catch up. When Blow-Up appeared on the scene with not one, but 3 topless ladies - not to mention countless scantily clad ones - in very compromising positions, it must have caused one hell of a stir.
With all this sexual tension, the main point to the story takes a bit of a back road, as Thomas flits around exposing everyone to his eccentricity. Again, this would cause the film to receive further hate, but again, the film is more about how to interpret Thomas' life.
In an ironic twist, the film's storyline ends up being much like the film itself in that Thomas ends up seeing what he wants to see and interprets it like he wants to. For this, Antonioni should be commended.
For me, not quite a 5-starrer, but certainly worth a watch... if you can stick it.