The body-swap comedy has a long Hollywood lineage, from Freaky Friday to Vice Versa to the recent 18 Again. The latest variation on this evergreen theme unites the director David Dobkin, best known for Wedding Crashers, with the screenwriters Jon Lucas and Scott Moore of The Hangover fame. In terms of lowbrow jokes about bodily functions and men behaving badly, that is quite some pedigree. So it comes as no surprise when the opening scene of The Change-Up sets the tone with a crying baby, a full nappy and a very unsavoury late-night snack. Yuck. Bateman plays Dave, an overworked Atlanta lawyer with a devoted but neglected wife, three young children and a luxurious suburban home. Reynolds co-stars as Dave\'s former childhood friend Mitch, an emotionally immature part-time actor with no ties, lots of casual girlfriends and a playboy bachelor lifestyle. Although both men are in their 30s, Dave is already deep into middle age while Mitch still lives like a perpetual teenager. Until one night when both express envy for each other\'s life in the middle of a mysterious thunderstorm and - kapow! - they magically wake up in each other\'s bodies. And so begins a roller-coaster ride of knockabout farce, crossed wires and family friction. On first impression, The Change-Up feels like a typically laddish, sub-Judd Apatow affair. The female characters, including the Apatow veteran (and real-life wife) Leslie Mann as Dave\'s long-suffering wife Jamie, certainly feel like thinly written male fantasies. Mann is underused in her shrill caricature role, as is the great Alan Arkin as Mitch\'s estranged father. But the film soon rises above these generic elements thanks to its brisk pacing and wise-cracking script, which leave little time to dwell on its preposterous plot and absurd characters. The comic chemistry between Bateman and Reynolds is also enjoyably sparky, even if the seven-year age gap between the two actors occasionally shows on screen. More often cast as the sarcastic straight man, Bateman is especially good in an unusually manic role. Although some of the bad-taste jokes feel forced, a couple of extended comic set-pieces almost justify the price of admission on their own. A quick-fire montage in which Dave-as-Mitch teaches Mitch-as-Dave the punishing rules of parenthood and marriage is an exemplary lesson in sharp-witted matrimonial satire. But the real stand-out sequence involves the first time Mitch-as-Dave wakes up in the small hours to feed his two screaming babies, recklessly exposing them to a catalogue of lethal dangers, from electrical sockets to sharp knives to food blenders. Tapping into every parent\'s worst nightmares, this expertly choreographed scene recalls the best of the classic Home Alone comedies. The Change-Up earned mixed reviews and lukewarm box-office returns in the US and Europe. It is tempting to blame this on the disappointingly sentimental finale, with Dave and Mitch predictably restored to domestic harmony after belatedly grasping the groaningly obvious grass-is-greener, be-careful-what-you-wish-for message. But whatever its flaws, Dobkin and his likeable leads still manage to deliver a decent hour of irreverent, mischievous and high-energy comic zing before the inevitable last-act decline arrives. And sometimes, an hour is enough.