The year is 1954. U.S. Marshal Teddy Daniels and his new partner, Chuck Aule, have come to Shutter Island, home of Ashecliffe Hospital for the Criminally Insane, to investigate the disappearance of a patient. Multiple murderess Rachel Solando is loose somewhere on this remote and barren island, despite having been kept in a locked cell under constant surveillance. As a killer hurricane relentlessly bears down on them, a strange case takes on even darker, more sinister shades—with hints of radical experimentation, horrifying surgeries, and lethal countermoves made in the cause of a covert shadow war. No one is going to escape Shutter Island unscathed, because nothing at Ashecliffe Hospital is what it seems. But then neither is Teddy Daniels.
This hospital is located on Shutter Island, with a geography reminiscent of the Alcatraz island prison off the coast of San Francisco. It is only reachable by boat.
They must investigate the unusual disappearance, from a locked room, of a patient who has been institutionalized after drowning her three children. But Daniels quickly develops suspicions about the staff at Ashecliffe, headed by Dr. John Cawley and Dr. Jeremiah Naehring, a German with a past possibly related to Nazi medical experiments in concentration camps. Daniels believes Cawley and Naehring enroll the inmates of Ashecliffe in psychological experiments aimed at mind control, using a combination of treatments with drugs and surgeries.
But as events unfold, deeper revelations ensue and, after a series of dreams and hallucinations, Daniels himself appears to be mentally ill and, in fact, just one more inmate at Ashecliffe.
Daniels’s partner, Chuck, disappears and then returns as one of the staff doctors. He has been helping to stage the storyline of Daniels as a U.S. marshal as part of an experimental treatment to help break through the delusions Daniels constructs for himself as protection from the reality of multiple traumas he has suffered.