Shutter Island is a 2010 Martin Scorsese film of the neo-noir psychological thriller genre, based on the 2003 novel by Dennis Lehane’s. It stars Leonardo DiCaprio, Mark Ruffalo, Ben Kingsley, and Michelle Williams.
The film centers around US. Marshals Teddy Daniels and Chuck Aule. In 1954, they travel to Shutter Island to visit the Ashecliffe Hospital for the criminally insane to investigate the disappearance of one of the patients, Rachel Solando. She was there for drowning her three children.
They arrive just before a huge storm that prevents them to return to mainland for a few days. They take advantage of this time to investigate, but the staff is not cooperative. John Cawley, the lead psychiatrist doesn’t turn over records, and they learn that her doctor, Lester Sheehan, left immediately after Rachel’s disappearance.
They’re also told Ward C is off limits for them and that there’s no need to search the lighthouse because it has already been done. Teddy finds all of this highly suspicious, confiding in his partner about it.
During the time at the hospital, Teddy starts suffering from migraines and has waking visions of his experiences at WWII, particularly the liberation of concentration camp Dachau. He also has nightmares about this wife Dolores, who was killed in a fire set by Andrew Laeddis.
He finds that Solando is still on the island, and so is Laeddis, who everyone claims has never been there. It’s revealed that Teddy’s true motivations for taking the case were to find Laeddis. Later, Solando was found inexplicably, prompting Teddy to become even more suspicious.
He then decides to break into Ward C, where one of the patients claims the doctors have been experimenting on patients, even lobotomizing them in the lighthouse. The patient also warns that everyone on the island is playing an elaborate game designed specially for him, including his partner.
Teddy regroups with his partner and they head to the lighthouse by climbing the cliffs, but they’re separated. Teddy later sees what he believes to be his partner’s body on the rocks below, but by the time he gets there, the body is gone. However, he finds a cave where the real Rachel Solando is, and he finds she’s a former psychiatrist who discovered the experiments. But before she could do anything to stop them, she was forcibly committed.
Teddy returns to the hospital but doesn’t find his partner and he believes his in the lighthouse. He gets there, and Cawley’s waiting for him to reveal that Teddy is actually Andrew Laeddis, their most dangerous patient. He’s been incarcerated for murdering Dolores, who suffered from manic depression and drowned their three children.
Because he was unable to save them, he went insane and he denied the entire experience in his mind. His entire experience on the island for the past few days has been designed to get Teddy to finally come to terms with reality. Overwhelmed by all this, he faints. When he wakes up, he’s questioned and tells the truth about his life.
However, Cawley notes he accepted the truth before, but quickly regressed. If he regresses again, he will be lobotomized, since this last try at the experiment was the last chance to save him. Laeddis is later seen relaxing on hospital grounds, but calls Dr. Sheehan “Chuck” again, which means the experiment has failed.
Sheehan shakes his head at Cawley to signal this, and Cawley gestures to the orderlies to take Laeddis to be lobotomized. The twist is that before the orderlies come from him, Laeddis asks Sheehan, whether it’s worse to live as a monster or die as a good man. He readily accepts his fate and leaves with the orderlies of his own free will, leading us to believe he chose his destiny in the end.