Variety reports:

Martin Scorsese and Leonardo DiCaprio will reteam early next year on "Shutter Island," a Laeta Kalogridis-scripted adaptation of the Dennis Lehane novel.
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Drama is set in 1954, with DiCaprio in final talks to play U.S. Marshal Teddy Daniels, who is investigating the disappearance of a murderess who escaped from a hospital for the criminally insane and is presumed to be hiding on the remote Shutter Island.