Martin Scorsese's adaptation of Dennis Lehane's Shutter Island represents yet another striking examination of guilt and the quest for redemption by the director, this time through the lens of a twisty psychological thriller. The film artfully displays how effortlessly Scorsese can weave his recurring obsession with these concepts into one of the few genres he hasn't tackled. The movie opens in 1954 as World War II veteran and current federal marshal Teddy Daniels (Leonardo DiCaprio) and his new partner, Chuck (Mark Ruffalo), ferry to Shutter Island, a water-bound mental hospital housing the criminally insane. They have been asked to investigate the disappearance of Rachel Solando (Emily Mortimer), a patient admitted to the asylum after she murdered her three children. As Teddy quizzes Dr. Cawley (Ben Kingsley), the head of the institution, he begins to suspect that the authorities in charge might not be giving him the whole truth, and that a terrible fate may befall all the patients in the spooky Ward C -- a unit devoted to the most heinous of the hospital's inmates. Complicating matters further, Teddy has a secret of his own -- the arsonist who murdered his wife is incarcerated on Shutter Island. Driven to confront his wife's killer, and stranded on the island because of a hurricane, Teddy must unravel the secrets of the eerie place before succumbing to his own madness. This is far from the most original plot ever devised, but Scorsese and company so insistently pile on layers of paranoia and dread that you quickly forgive the familiarity. Teddy is haunted by nightmares about his late wife, as well as what he saw as an infantryman when he was part of a squad that liberated the Jews imprisoned at Dachau. There are ongoing references to the hydrogen bomb, and the patients are spooked by this new-fangled contraption they've heard about called "television" -- where pictures and voices fly through the sky. The movie makes modern life -- or at least modern life in the '50s -- feel panic-inducing. And make no mistake, this is a movie designed to instill paranoia. The stylized clothing and speech -- everyone talks like they're in a movie from the '50s -- act to keep us distanced from everything, so that we never can shake the feeling that something just isn't right, and all the mysterious visions and talk of horrific experiments on the patients make the fear unrelenting. Even the sound design adds to the terror in a variety of ways; a subtle echo makes the inside of the buildings feel cavernous, and there are long stretches of silence disconcertingly punctuated by sudden sound effects. At the center of it all is Leonardo DiCaprio, an actor who after nearly 15 years of excellent work can still surprise with his talent. His performance is difficult to praise without ruining some of the movie's suspense, but as the final credits roll you can't help but think back on what you've seen and marvel at how complicated his role is; what initially seems like a fairly one-note performance blossoms into a fully realized portrait of a good man beaten down by what he's experienced. But he's far from the only standout in the cast: Mark Ruffalo provides flawless support as his partner, Ben Kingsley savors every morsel of his dialogue, and Patricia Clarkson delivers a show-stopping monologue about how easy it is to keep someone in an insane asylum with such intensity that it might be the scariest moment in the whole film. In addition to those fine actors, Scorsese and his casting director have filled out the supporting roles with actors recognizable as some of the scariest screen psychos in recent memory. Ted Levine (Buffalo Bill from The Silence of the Lambs) plays the head of security; John Carroll Lynch (the main suspect in David Fincher's Zodiac) portrays a guard; Jackie Earle Haley (the sex offender in Little Children, as well as the new Freddy Krueger) has a frightening and memorable scene as a patient Teddy knew from before; and Max von Sydow, as imposing and serious a figure as the movies have ever given us, plays a German doctor who may have ties to the Nazis. Scorsese deftly plays on our collective memory of these actors to maintain the sense that the threat to Teddy's safety is omnipresent. And it's not just the history of actors that Scorsese exploits, but movie history as well. Shutter Island is as much about Alfred Hitchcock's ability to build and maintain suspense and Jacques Tourneur's skills at scaring the audience with what is unseen as it is about finding a missing killer. But the style never gets in the way of the substance -- Shutter Island could be the first movie you've ever seen and it would still unsettle you. Even for those who early on feel they've figured out what's going on in the movie -- and the clues are right out in the open -- Scorsese isn't relying on a shocking revelation to make the film worthwhile. In fact, the story ends on a disturbingly ambiguous note that highlights how much more he has on his mind than simple chills. Scorsese is right back where he always is, searching for redemption.