The film opens with the close-up of a hand holding a Polaroid picture, in which we see a man lying on the floor photographed above the waist from his back. His head rests on a pool of blood, some of which is scattered on the wall close-by.
The colours of the Polaroid slowly fade away and the person holding it starts to flap it. Contrary to our expectations, the colours fade more with the flapping and gradually the picture becomes all white. The camera now turns to show us the man who is holding the photograph; first he puts it back to the Polaroid camera, then he takes a shot. Slightly more than a minute into the opening scene, it is clear that this part is running backwards, which foreshadows the most conspicuous stylistic element used throughout the film. From this scene onwards coloured scenes will be ordered backwards while the black and white will run normally. The following shots are almost like still images: first of blood running down, then of an empty bullet shell and finally of a pair of glasses. Then there is the same dead body from the photograph, the victim, with his head resting in the same pool of blood.
A gun jumps up from the floor into the man’s hands and all these images come to life. The blood and glasses go back to the victim, the bullet shell to the gun and with the sound of the shot, the victim is alive again. The scene cuts to black and white from here. The killer is in a hotel room now. Looking perplexed he asks himself where he is. Next starts another scene in colour, in which, surprisingly, there is the victim greeting the killer. Initially Memento provides no information as to where and when these scenes are taking place and how they are linked. The film continues to switch between black and white, and coloured scenes while the audience attempts to understand the logic behind their organisation.