The story has Depp hounded by a weirdo (John Turturro) from the rural South who claims Depp plagiarized one of his stories. Problem is, the stranger wrote his story years after Depp wrote the supposedly stolen one. Perhaps King is trying to work out his own artistic dilemma, wherein he routinely rehashes his older stories to make new ones. Which is fine if the new ones are better, or contain fresh twists, but in King's case, they're pat and familiar.
Certainly that's true of Secret Window it's so predictable that I only held on in anticipation of some amazing twist that would totally blow my mind. But the big twist turns out to be the very thing you probably predicted from seeing the trailer: Turturro is simply a representation of Depp's self. Yeah, that's right his "dark half." Didn't Fight Club render that twist obsolete five years ago?
It's not notable in any respect, including Depp's performance. Once again, we are forced to ask ourselves why, if Stephen King's stories are so great, can't a decent film be made out of one of them? The answer, of course, is that the stories aren't so great.