A recurring feature in Nolan's films is the intelligent analysis of what goes on inside the human mind. The way he puts this across is outstandingly creative, and there's no better example of this than Memento. To put the audience on the same level as the main character, who is unable to form new memories after being attacked in his house, the story is told backwards. The film is made up of a number of short scenes played out in reverse chronological order, gradually revealing the truth about each of the characters we've already met; the truth that Leonard, the damaged protagonist, has already forgotten. It's a genuinely interesting way of doing things, and, like the dream world in Inception, it takes us inside the brain. At the start of the film, the audience is just as confused as Leonard, and only finds everything out at he same pace as him.
Because the smallest detail in one scene could have caused one of the major event seen earlier on in the film, Memento punishes those whose concentration wanders for a minute or two. Characters who you always assumed were on Leonard's side turn out to be taking advantage of his condition, and vice versa. The words that Leonard has written underneath his Polaroid pictures change meaning. Nolan has crammed as many twists as physically possible into 113 minutes, and so it is necessary to keep your wits about you for the entire thing. If you do manage it, though, you'll get a hell of a reward by the end credits.
Before not too long, you'll have worked out that Leonard is after a mysterious man named John G, who supposedly raped and murdered his wife in front of his eyes during the same attack where he lost his ability to form new memories. We follow him as he moves around town, meeting new contacts and taking their photos so he is able to remember them when he sees them again. To confuse things further, each reverse-chronological main scene is separated from the next by a series of scenes shot in monochrome and shown in chronological order, with Leonard in his hotel room. These two timelines eventually meet by the end. If you can understand those last two sentences, you'll have no trouble with Memento.
Guy Pearce's Leonard strikes exactly the right notes, being just as determined and constantly perplexed as he should be. The acting, for the most part, does take a back seat to the story and script, though. What starts like a simple murder mystery (albeit a why-did-he-do-it rather than a whodunnit) ends as something much more fascinating and shocking. A deceptively simple way of telling the story is worked to its full potential by Nolan, making Memento one of the most enjoyably unique and cerebral movies of the 21st century.
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