Arguably, Martin Scorsese's Shutter Island with Leonardo DiCaprio is one of the most perplexing films, with a convoluted plot and an ambiguous ending that left many viewers bewildered. What was it? Who is the real protagonist? A killer, a madman, or a victim? Well, we've decided to break it down and put all the pieces together for those still unsure.
The film follows U.S. Marshal Teddy Daniels (DiCaprio) as he arrives on an island to investigate the disappearance of a patient from a psychiatric hospital. But the deeper he digs, the harder it becomes to distinguish what’s real and what is merely a product of his imagination. Teddy encounters numerous strange events and mysteries, and his confidence in his investigation begins to unravel.
In the film's climax, it's revealed that Teddy is, in fact, Andrew Laeddis, a patient at the psychiatric hospital. He created the illusion of an investigation to cope with the guilt of murdering his wife in a fit of rage after she drowned their children. His entire “investigation” was merely part of his psychosis.

The film ends with Teddy’s line: "Which would be worse: to live as a monster, or to die as a good man," which reflects his attempt to avoid confronting the painful reality of his past.
The final scene leaves us questioning whether he found the strength to accept his guilt or chose to remain in his delusion, escaping the horrors of his past.