Pieces don’t quite come together in this thriller

You sense you’re in trouble when a movie resorts to selling itself with a description like “in the space between desire and fear, reality and illusion, life and death lies a whole other alternate world.” Not that there’s a better way to describe it. That “whole other” basically sums it up.

With “Stay,” Marc Forster (“Monster’s Ball,” “Finding Neverland”) tries his hand at a psychological thriller and comes up with a perversely stylish tangle of loose ends unencumbered by logic. A dream about a dream in which everybody seems to have a limitless clothing budget and a degree in interior design, nothing is as it seems in David Benioff’s script, but nothing is connected, either.

Sam Foster (Ewan McGregor), a New York shrink who, for reasons that never become clear, dresses like a Yale rugby player circa 1924, wakes up from a nightmare and hurries off to meet a new patient whom he has inherited from a colleague (Janeane Garofalo). The patient is a disturbed young art student named Henry Letham (Ryan Gosling), who announces he plans to kill himself on his 21st birthday -- just three days away.

Henry is racked with guilt over the death of his parents, whom he claims to have killed. But he also mysteriously reappears in Sam’s dreams, sitting cross-legged on the Brooklyn Bridge as his car burns behind him; and appears to be able to foretell the future. (Is this what’s meant by “fashion-forward?”) Later, he unnervingly identifies Sam’s friend, Dr. Leon Patterson (Bob Hoskins), as his dead father.

Sam’s girlfriend Lila (Naomi Watts), meanwhile, keeps angling to meet Henry. A painter and former patient of Sam’s, she wants to talk to him, suicidal depressive to suicidal depressive. “Tell him there’s too much beauty to quit,” she tells Sam, when he refuses.

She’s right about that. If there’s one thing to be gleaned from “Stay,” it’s that the netherworld between life and death and illusion and reality is exactly like one giant issue of Wallpaper. As the streets become populated with identically dressed twins and triplets, minor moments replay for no apparent reason, and reality and fantasy merge in soft-serve spirals, it becomes clear that Sam and Henry’s identities are starting to merge.

Sam clears his schedule to race around a dream-like, hyper-stylized New York trying to find out why his Lila is calling him Henry and why Henry’s dead mother is trying to feed him leftovers from her empty fridge. But the why and how of it never come together in any sort of satisfactory way.

It’s a shame, really, because few things are more enjoyable than a well-put together psychological puzzle whose pieces actually fit. But even though McGregor and Watts are nice to look at, and obligingly submit to more costume changes than the situation requires. (McGregor’s pants, which perplexingly hover well above his ankles throughout the movie, add to the general air of mystery), the movie hinges on a cheat of an ending, and not a very original one, either.

The final twist does more to unravel what’s come before than to tie it all together, making what’s come before feel like a cosmopolitan goose chase.

*

‘Stay’

MPAA rating: R for language and some disturbing images

Times guidelines: Contains car accident imagery and some scary moments

20th Century Fox presents. A Regency Enterprises presentation. A New Regency production. Directed by Marc Forster. Written by David Benioff. Producer Arnon Milchan, Tom Lassally, Eric Kopeloff. Executive producers Bill Carraro, Guymon Casady. Director of photography Roberto Schaefer. Production designer Kevin Thompson. Editor Matt Chesse. Music by Asche & Spencer. Running time: 1 hour, 39 minutes.

In general release.