In "Memento," the real killer is revealed to be Teddy, played by Joe Pantoliano. Throughout the film, Leonard Shelby, who suffers from short-term memory loss, is on a quest to find his wife's murderer, believing it to be a man named John G. However, as the story unfolds, it becomes clear that Teddy has been manipulating Leonard for his own gain and was involved in the events leading to his wife's death. The film's intricate narrative structure highlights themes of memory, identity, and the nature of truth.

"Memento" and "Ghajini" share a similar premise involving characters with short-term memory loss seeking vengeance, but they are not the same. "Memento," directed by Christopher Nolan, features a non-linear narrative where the protagonist, Leonard, uses tattoos and notes to track down his wife's murderer. "Ghajini," directed by A.R. Murugadoss, is an Indian film inspired by "Memento," but it incorporates Bollywood elements and a more straightforward storyline. Both films explore themes of memory and revenge, but they differ significantly in style and execution.

In "Memento," the main twist is revealed at the end: Leonard Shelby, the protagonist suffering from short-term memory loss, has been manipulating his own quest for revenge against the man he believes killed his wife. Throughout the film, he relies on notes and tattoos to track information, but it's ultimately disclosed that he has already killed the man he sought, John G. The narrative structure, which plays in reverse, emphasizes his struggle with memory and identity, culminating in the realization that he is trapped in a cycle of self-deception.

Yes, "Memento" is often considered a confusing movie due to its unique narrative structure. Directed by Christopher Nolan, it tells the story of Leonard Shelby, who suffers from short-term memory loss. The film unfolds in a non-linear fashion, with scenes presented in reverse chronological order, interspersed with black-and-white sequences that provide context. This structure mirrors Leonard's disorientation and challenges viewers to piece together the plot, making it a thought-provoking experience that encourages multiple viewings to fully grasp its intricacies.