Leonard Shelby

Leonard Shelby is the protagonist of the 2000 film Memento who suffers from anterograde amnesia, rendering himself unable to remember anything since the night of his wife's tragic death. He seeks revenge against a "John G.", which triggers the story's plot.

Role in the Film
Aided by Teddy, Leonard seeks to find a "John G.", one of the criminals that attacked him and murdered his wife prior to the events of the film. But due to his anterograde amnesia, Leonard is forced to keep a record of every note he keeps via Polaroid photographs, tattoos, and other scribed notes. Throughout the plot, he shares his account of a former client Sammy Jankis who suffered from the same condition and accidentally murdered his wife by her attempts to jog his memory by providing insulin shots. In the meantime, Leonard has been trailing a "John G." which leads him to encountering a resentful bartender named Natalie. She manipulates him into attacking and driving a man named Dodd out of town. He also murders Jimmy Grantz under the impression that he is the "John G." he is seeking and photographs his body.

But as the plot continues, many truths are revealed. Leonard has murdered several individuals by the name of "John G.", helped by Teddy throughout each case. The proof comes from a Polaroid photograph indicating that Leonard has already allegedly killed long before. Teddy also claims that Sammy Jankis' story is really just Leonard confusing his accidental murder of his wife following the attack with the story of a con artist. What's more, Natalie's resentment towards Leonard stems from Leonard driving her boyfriend Jimmy Grantz's car and wearing his clothes. Natalie also reveals that Teddy's real name is John Edward Gammell, leading Leonard to distrust and later kill Teddy as seen in the beginning of the film. In the end, Leonard is left without his one ally in the world and it is noted that he will forget the murder and once again seek a "John G."

Observations of the Ending
At the end, there are two possible interpretations for Leonard Shelby as a tragic anti-hero/villain. In the former, everyone is suspect in the course of the film. Particularly, there is question regarding Teddy's help to Leonard. Although revealed to be an undercover officer, Teddy possibly may have used Leonard as a pawn to fish out and kill criminals or those interfering with his plot. His claim that Leonard's accidental murder of his wife via insulin shots might also be suspect as well. Given the narrative's focus on Leonard, the suspicion is given weight due to lack of details. In this instance, Leonard would be a pawn of sorts, possibly freed from killing anyone else on Teddy's behalf.

The other interpretation is arguably more disturbing. One of the film's final revelations is that Leonard himself deliberately blacked out the police accounts of the attack and has burned previous photos of "John G." so as to start all over again. At the very end, Leonard muses that seeking his wife's killer has become his purpose in life, and questions how bad it can be to make one's own life purpose. He is then shown burning the Polaroid of Jimmy Grantz and purposely recreating Teddy as the new "John G." to pursue.