HispanicBusiness

The Change-Up poses a familiar question: What if I swapped lives with my best friend, who's totally different from me? The body switchers here are Mitch (Ryan Reynolds), a slacker man-child and would-be actor who coasts through a life free of responsibility, and Dave (Jason Bateman), a lawyer with a lovely wife named Jamie (Leslie Mann, charmingly helium-voiced as always), a beautiful home and three small children, two of them infant twins. After a drunken evening and some public urination (this movie's mildly obsessed with human waste, in both forms), the men suddenly find that they've traded places. Mitch, in Dave's body, turns up at home with Jamie, the kids and an imminent diaper emergency; Dave, in Mitch's body, wakes up in Mitch's scruffy apartment, wondering what comes next in a suddenly unscheduled life -- and is horrified to learn that his day's work is to star in a "lorno" (light porno) movie.

Need I tell you that despite many wacky missteps, the experience causes the duo to become better men? Mitch, after some trial and error, learns how to be a good husband; Dave eventually learns to relax; and Jamie learns that weird things happen sometimes when two men go out for the evening.

It's a reasonably sweet message, but made less so by the laziness of the filmmaking. Director David Dobkin, working from a screenplay by Jon Lucas and Scott Moore ("The Hangover"), apparently never saw a poop joke he didn't like, and even the casting seems lackadaisical. Reynolds and Bateman are likable, and ably convey golden-boy slackertude and uptight midlife crisis respectively -- but did it occur to anyone involved that, for playing a pair of lifelong friends, the two men don't look anywhere near the same age?

Ultimately, "The Change-Up" offers a few laughs, and fewer surprises.