In Yes Man, as you must know by now, Jim Carrey is a walking wet blanket transformed into a poster child for positivity. His Carl Allen is a bank-loan manager stuck in sourpuss limbo after a short-term marriage heads south. A chance encounter with an old pal (John Michael Higgins) leads him to a self-help seminar, during which the empowerment guru (a terrific Terence Stamp) makes him promise to drop his negativity.

This isn’t easy, since the only fun Carl gets is from creative nay-saying. But his first attempt at flowing with the go leads him to a date with the adorable Allison (an effortlessly charming Zooey Deschanel), lead singer of an art band called Munchausen by Proxy. Instant head-nodding also leads him to guitar lessons, Korean-language classes, and a Persian mail-order bride—all of which show up in amiable, if not quite hilarious, set pieces.

I wish that director Peyton Reed (The Break-Up), working with a team-written script adapted from a humorous memoir by British TV’s Danny Wallace, had put more character into the comedy. Still, he provides an illusion of depth through a hip soundtrack, arresting L.A. locations, and unusually smart casting. Those acting well beyond the demands of the material also include Bradley Cooper as a surprisingly patient best friend and Flight of the Conchords’ Rhys Darby, as the nerdy boss who eggs on the new Carl.

A subplot with our silly-faced hero’s ex-wife (Molly Sims) feels tacked-on, and the filmmakers don’t seem to know what they’re saying about his behaviour when the FBI gets involved. But, hey, Carrey’s just there to deliver the concept, and he never says no to that.