Memento explained: What really happened in Christopher Nolan's cult classic?

The movie follows the story of Leonard Shelby (played by Pearce), a former insurance investigator suffering from anterograde amnesia due to a head injury sustained while trying to save his wife from a home invasion.

But with an unusual narrative structure and a stunning final twist, you may be left with some questions after watching the film. So read on for our full Memento explainer, including timeline and ending recap.

What is anterograde amnesia?

This is a neurological condition where the sufferer is unable to create new memories after an event that caused the amnesia. This results in the complete inability to recall recent events (akin to a more severe form of short-term memory loss). However, long-term memories (ie, from before the event that caused the amnesia) remain.

The non-linear style of storytelling reflects the fragmented nature of the lead's condition meaning the viewer is as much of a detective as Leonard Shelby is himself.

Memento is presented in reverse chronological order. The audience is immersed in Leonard's fragmented perception of reality as he struggles to piece together his life and solve the mystery of his wife's murder. Due to his condition, Leonard relies on a system of tattoos, notes, and Polaroid photographs to remember vital information and the people he encounters.

The film intertwines two parallel storylines: one in black and white and one in colour. The black and white scenes move forward chronologically, narrating Leonard's meetings with Teddy (Joe Pantoliano), a police officer assisting him, and Natalie (Carrie-Anne Moss), a woman who claims to be helping him. The colour sequences, however, move backward in time and showcase events leading up to Leonard's wife's murder.

Easy-to-read Memento timeline

1. Pre-incident: Leonard Shelby is an insurance claims investigator who lives a normal life with his wife. He is robbed at his home, resulting in injury to his head, causing him to suffer from anterograde amnesia.
2. Incident: Leonard's wife is murdered during the robbery, leaving him with a deep desire for vengeance. However, due to his amnesia, he is unable to remember any new information for more than a few minutes.
3. Post-incident: Leonard sets out on a relentless quest to find his wife's killer. He begins to rely on polaroid pictures and notes to remember crucial information since his memory resets every few minutes. He tattoos important details on his body to ensure he never forgets.
4. Leonard meets Natalie, a bartender who seems to genuinely care for him. She provides him with information about a drug dealer named Dodd, whom he believes could be his wife's killer. Leonard kills Dodd, convinced that he has avenged his wife's death.
5. Leonard becomes involved with Teddy, a former police officer. Teddy uses Leonard's condition to his advantage, manipulating him for his own gain. Teddy pushes Leonard to believe that Jimmy, another person connected to his wife's murder, is the real killer. Leonard kills Jimmy.
6. The truth about Teddy: It is revealed that Teddy has been manipulating Leonard all along. Teddy is an undercover officer who had already solved Leonard's wife's murder case and was using him to his own advantage. Teddy manipulates Leonard into believing he should kill another person named John G, framing him as his wife's murderer.
7. The climax: Leonard tracks down and kills "John G" but discovers later that the real John G died a year before his wife. Leonard's desire for revenge becomes an endless cycle, as he is unable to remember the truth and is prone to manipulation due to his memory loss.
8. Final scene: Leonard comes to the profound realisation that his condition has been exploited by others for their gain. Despite knowing the truth, he decides to erase his own progress and allow himself to continue living in a cycle of ignorance, as he fears the pain that the truth might bring. The film ends with Leonard's determination to continue seeking revenge, even if it means relying solely on his fragmented memory and dubious notes.

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Remember Sammy Jankis – what's that all about?

The story of Mr Samuel R Jankis serves as a parallel to Leonard's and is obsessively recalled throughout the film. According to Leonard, Sammy had been in an accident and suffered damage to his hippocampus (part of the brain structure that has a major role in learning and memory), leaving him unable to make new memories.

Leonard was called in by Sammy's wife to assess the situation as medical bills were mounting (in his role as insurance investigator). Their claim was unsuccessful and Sammy's wife went to extreme measures to test her husband. As she required insulin injections, which he would administer, Mrs Jankis tested him by seeing if he would give multiple injections within the space of an hour. Sadly, his condition meant that he couldn’t remember giving the previous one so continued to inject his wife resulting in a fatal overdose.

However, Teddy stated that while Sammy Jankis did actually exist he did not have a wife. And, more besides, Leonard discovered during his investigation that Sammy was faking his condition. It was Leonard's wife, according to Teddy, who had diabetes. Leonard was projecting his experiences and the death of his wife onto Sammy when retelling the story.

The plot of Sammy serves to blur the lines between truth and fiction, challenging Leonard's perceptions and making him question the reliability of his own memories and motivations. It's left up to the audience to debate if Sammy is real as remembered or simply a figment of Leonard's mind.

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