For all of its explanatory third act revelations, it remains proudly and engagingly ornate - a smokey work full of style and bare-knuckled moodiness that eventually outworks its deficiencies.
The film begins with a boat emerging from the fog, a detective (Leonardo DiCaprio) is dripping water from his face, pleading with his reflection to "pull yourself together." As the ferry approaches an island, a seemingly endless supply of skulking, strong-jawed security guards greet the detective and his partner (Mark Ruffalo) to the sounds of the deep, probing and conspiring notes of Krzysztof Penderecki's Symphony No. 3. As if you didn't know, something is amok here on Shutter Island.
Like the repeating tones of that particular musical piece (which both opens and closes the film in tidy fashion), Shutter Island relies on similar repetition in order to submit the audience into a state of psychological unrest and disillusionment. Flashbacks and dream sequences (some of them on top of one another) rule the days and sleepless nights of the confounded Teddy Daniels (DiCaprio).
And essentially, Shutter Island turns out to be Scorsese's arsenal of well-oiled gears and gadgets wound up like clockwork to run something seemingly less demanding. Teddy's plight is depicted initially like a B-movie genre trope before subsequent viewings and digesting reveals something heartier - this film isn't about fooling you and holding a carrot in front of your face, it's about the roots of violence, anger and psychological instability. (Not to mention a slight commentary on the condition of post-WWII mental health care.)
For me, Shutter Island is a fully alive and compelling genre piece. It may feel at times like a film that wallows in its own deceptions and technique, trying desperately to surprise the audience, but by the end, it becomes something with more weight, ambiguity and old-fashioned directorial commitment than anything we're likely to see this year. It may not be Scorsese's The Shining - it's too slavish to Dennis Lehane's source novel for that - but after much gestation, I believe it could be the director's greatest work in over two decades.