Memento

Memento chronicles two separate stories of Leonard, an ex-insurance investigator who can no longer build new memories, as he attempts to find the murderer of his wife, which is the last thing he remembers. One story line movies forward in time while the other tells the story backwards revealing more each time.

Memento is a 2000 psychological thriller film written and directed by Christopher Nolan, adapted from his brother Jonathan's short story "Memento Mori". It stars Guy Pearce as Leonard Shelby, a former insurance fraud investigator searching for the man he believes raped and killed his wife during a burglary. Leonard has anterograde amnesia, which he developed as a result of the severe head trauma during the attack on his wife. This renders his brain unable to store new memories. To cope with his condition, he maintains a system of notes, photographs, and tattoos to record information about himself and others, including his wife's killer. He is aided in his investigation by Teddy (Joe Pantoliano) and Natalie (Carrie-Anne Moss), neither of whom he can trust.

Source: Wikipedia