By the time Rachel is found by Deputy Chief Warden McPherson (JOHN CARROLL LYNCH), the marshals have come to suspect that there is a lot more going on at Shutter Island than meets the eye. A hurricane strands them there, with no ability to communicate with the mainland.

Eventually, we come to learn that Teddy volunteered for this assignment. Haunted by visions of his military service in World War II and the loss of his wife (MICHELLE WILLIAMS) two years earlier in an apartment building fire, he suspects that the man who was responsible for the blaze is a patient in the hospital's infamous Ward C. What he finds there, though, is more than he bargained for.

The film is derivative and grossly self-indulgent in spots, but it's also entertaining and perversely operatic. Scorsese knows precisely what he wants here and he knows exactly what he is doing as well. My bet is he had more fun making this movie than his late four or five films combined.

The story is set in 1954. Leonardo DiCaprio and Mark Ruffalo play Teddy Daniels and Chuck Aule, a couple of federal marshals assigned to look into the disappearance of Rachel (Emily Mortimer), a woman who murdered her own children, from her locked cell on Shutter Island. The creepy, Alcatraz-like place is something out a feverish Hitchcockian dream, complete with a foreboding lighthouse and a Gothic-looking, restricted ward where the "worst of the worst" prisoners are kept away from the "less violent" killers and rapists.

Everyone has secrets. Everyone! But most of all, Teddy is hiding deep, dark regrets from his past and is haunted throughout the film by dreams, nightmares and actual visions of his wife (Michelle Williams) who perished in a fire two years later. He also keeps flashing back to an especially tragic episode during his military service in World War II when his battalion liberated one of the Nazi concentration camps.

As Teddy and Chuck's investigation progresses, we come to learn that all is not what it seems on Shutter Island. Have the marshals been summoned here? Or were they lured there? Who is the mysterious "67th patient" that Rachel wrote about in a cryptic note? What is the secretive Dr. Cawley (Ben Kingsley) hiding from the investigators? Is his colleague, Dr. Naehring (Max Von Sydow), a former Nazi who did experiments on Jewish prisoners? Or is he who he says he is, a German immigrant who cares for the criminal insane?

Scorsese gets around to answering all those questions. I give him high marks for his visual flourishes, his fantastic use of locations, and his spot-on casting. This is a flick that hinges on people looking and acting secretive, all the while keeping the audience off-balance as to what is really going on in the film. The actors are all up to the challenge.

In addition to the well-known leads, the supporting players read like a Who's Who of movie sickos from the last 20 or so years including: Ted Levine (Buffalo Bill of "The Silence of the Lambs"), absolutely malevolent in a small role as the film's mysterious warden; John Carroll Lynch (the main suspect in "Zodiac"), vaguely channeling Clancy Brown from "The Shawshank Redemption" as Shutter Island's deputy warden; and Jackie Earle Haley (the kid molester from "Little Children") in a memorable cameo as a deranged patient.

What keeps the film from being great is its unwieldy running time. At two hours and 20 minutes, it is simply way too long in telling what is ultimately and essentially a big-screen "Twilight Zone"-"Outer Limits" episode. Rod Serling told this kind of story and told it better in under 30 minutes decades ago. The film's final act is particularly drawn out, lingering on plot details, big revelations and practically flashing "GOTCHA!" at the viewer like a studio-audience "Applause Please" sign.

"Shutter Island" isn't quite as clever or as creepy as the great director conceived it as. But compared to 95 percent of the other dreck out there, it's insanely watchable … heavy emphasis on the insane. As a riff on other movies, I got what was going on with the director even if I didn't quite "get" was going on with the characters until late. I rate it a 6.5 out of 10. (T. Durgin)