13 years after its release, Shutter Island continues to be must-watch film for anyone that appreciates psychological thrillers. This is despite it being one of Martin Scorsese’s most divisive movies to date, mainly due to its plot twist ending that still fuels some debate.

Based on Dennis Lehane’s book of the same name, Shutter Island’s music and its noir setting are perfect to push viewers into believing something is off at Ashecliffe Hospital from the very start, much like a typical horror film would. Nevertheless, the very dynamics of U.S. Marshal Teddy Daniels and his partner Chuck Aule’s (Mark Ruffalo) relationship help foreshadow some of the story’s many twists and turns, which is probably why Shutter Island can be just as enjoyable on a second viewing as in the first.

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What Happens at the End of Shutter Island?

Shutter Island ending with orderlies in yard

After joining Teddy and Chuck for a few days of crime solving, it becomes easier to see that the protagonist's mental state is quickly deteriorating, with the only remaining question being whether that is down to Dr. Cawley’s (Ben Kingsley) scheming or Teddy's own troubled past. That said Shutter Island’s tone is put together perfectly so that the audience can’t truly commit to one side thanks to Teddy’s hallucinations getting worse with every passing minute.

Teddy does admit he was scarred after his wife’s death at the hands of some arsonist (Andrew Laeddis) who is known to be locked up at the Shutter Island facility, yet he never mentions the two had any children. In the flashback memories or dreams featuring Dolores (Michelle Williams), his wife dies, the audience can catch a glimpse of a lake view crucial to their story, but mostly, Dolores doesn’t want him to keep unraveling the mystery that lies before him.

Once Teddy is ready to admit his mind is definitely playing tricks on him, he decides to tackle the mysterious lighthouse to rescue Chuck from danger, only to come across Dr. Cawley patiently waiting for his plan to resolve. As Cawley informs him, Teddy is not a U.S. Marshal, instead, he is a patient at Ashecliffe where he has been for two years after killing his wife, who drowned their children during a mental breakdown episode.

Leonardo DiCaprio and Mark Ruffalo in Shutter Island ending

It’s the memory of his kids that really gets Teddy, or rather Andrew Laeddis, to admit that he did indeed kill his wife. Chuck is revealed to be his personal psychiatrist at Ashecliffe, who set up a convoluted simulation that could awaken his mind. Despite showing himself lucid towards the end, Andrew appears to go back to his Teddy persona, until he asks Dr. Sheehan whether it’s better “to live as a monster or to die as a good man?

Although Shutter Island explicitly tells the audience that Teddy/Andrew was detached from reality, that last line, as well as Dr. Sheehan’s failed attempt to call out for Teddy leaves it up to each and every one to interpret if DiCaprio's character willingly opted to be lobotomized out of the pain and shame brought on by his tragedy.

Are There Clues To Shutter Island's Ending?

Leonardo DiCaprio and Michelle Williams in Shutter Island dream

The overall ending for both book and movie leads to the same outcome, yet that ambiguity in Andrew’s final words doesn’t exist in Lehane’s writing. This was added to Shutter Island by screenwriter Laeta Kalogridis and Scorsese, though the author has chosen to interpret it as a rare moment of clarity from the protagonist before getting his lobotomy appointment.

Instances like this are spread out in many parts of the movie, as Shutter Island has several clues that hint at the ending, in fact, there are quite a lot, such as the attitude seen in Ashecliffe’s guards, orderlies and other patients. Teddy’s own dismissal of Chuck’s definitive proof to reveal who is patient 67 comes off as another example, and the same goes for his strange conversation with Ashecliffe’s warden.

Granted, plot points like the anagrams hidden behind the rule of fours Teddy and Chuck find in Rachael Solando’s room call for a larger reach and imagination, though Chuck’s mishandling of his government-issued firearm is perhaps the biggest tell in Shutter Island.

Leonardo DiCaprio waking up in Shutter Island plot twist

Shutter Island did great at the box office, and yet, even to this day, it’s one of Scorsese’s worst-reviewed movies, one that even makes some fans partly deny the official ending, as they believe Ashecliffe is indeed a nefarious place hiding human experiments.

As far as unreliable narrators go, Shutter Island’s Teddy Daniels is right up there with the best of them, with the film’s added spin of leaving Andrew’s true sanity up for debate helping it cement its legacy. Regardless of Lehane preferring his ending, this extra twist is certainly better implemented than American Psycho’s own spin on its origin novel.

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