This Ursula K. LeGuin story was already made into a film, whose fame was largely due to its unavailability for over a decade. Perhaps they decided the simplest thing was to make another version, but the interesting premise here is undermined by sluggish execution. Haas plays George Orr, a man who believes the world changes in response to his dreams, although he's the only one who can tell. His court-appointed shrink (Caan) is eventually convinced, and decides to take advantage: fame, fortune and an office with a view beckon. But manipulating someone's dreams isn't an infallible process, and you might not get exactly what you wish for.
Any film with sleep as a central plot-point is a potential minefield - watching the lead character go under is inevitably soporific, and it was a struggle to avoid losing consciousness ourselves. Adding to this is a generally low-key approach, though part of the film's impact is because you're left to spot some of the changes yourself. Haas delivers a delicately-placed performance as a man totally unprepared for the massive responsibility landed on him, though he's perhaps too understated - if I was responsible for a plague which killed tens of millions, I'd be more upset. While a mildly interesting rumination on the nature of reality and the strands of destiny, I suspect it works better on the page than on screen.