Leonard is a man who is struggling to put his life back together after the brutal rape and murder of his wife. The most significant manifestation of Leonard';s injuries is that his short-term memory has been destroyed. Leonard retains awareness that his wife was brutally murdered, however, and he';s convinced that the culprit still walks the streets. Leonard is obsessed with the notion of taking revenge against the man who has ruined his life, and he sets out to find him, getting help from Natalie, who appears to be a sympathetic barmaid, and Teddy, who claims to be Leonard';s friend, even though Leonard senses that he cannot be trusted..