Leonard is unable to create new memories because, due to a blow to the head, he has lost his short-term memory. This will not prevent him from investigating his wife's death, although he has to take photographs of everything around him and get numerous tattoos on his body to remember the details.The international breakthrough for director Christopher Nolan was thanks to this film whose narrative broke established rules to ensure that the editing reflected the disorder suffered by the protagonist, who is incapable of generating short-term memories.