Unlucky in love and desperate for a break, London journalist Iris (Kate Winslet) and LA-based Amanda (Cameron Diaz) swap homes for Christmas. The idea is to avoid men, but as Iris strikes a chord with Hollywood composer Miles (Jack Black), her brother Graham (Jude Law) introduces Amanda to the charms of the Cotswolds. The time is ripe for another big, squidgy romantic trifle from the director of What Women Want.
Poor Iris (Winslet). She is but a lowly writer for the Daily Telegraph whose heart has broken by a caddish colleague (Rufus Sewell). It's all she can do to drag herself home to her perfect Christmas-card cottage in rural Surrey.
Poor Amanda (Diaz). A hugely successful movie trailer-maker, she is now alone in her palatial Hollywood pad after throwing out her cheating boyfriend (Edward Burns).
Thank heavens for the interweb, where the love-forsaken and loaded can swap houses and escape from their terrible lives for a while.
Babbling to themselves incessantly, the girls are booked, packed and airborne within hours. It's as though they're being filmed...
On her first night in snowy England, Amanda is disturbed by Iris's tipsy brother Graham (Law). And who could resist that handsome-charming-little-old-me routine?
Not Amanda. Despite having sworn off men, she drags him into bed faster than a prostitute offering a winter sale.
Then they begin to get to know each other better, an excruciating process in which Graham's domestic responsibilities only come to light when it serves the plot.
Jaws can be unclenched slightly during the Stateside episodes, as Iris befriends doddery ex-screenwriter Arthur (Eli Wallach) while being won over by the musically amusing Miles (Black).
"Let's get this embarrassment over with", says Arthur. Wise and welcome words, but unfortunately preceded by over two hours of saccharine mind-rot.
Playing weak is not one of Winslet's strong points. As one of life's doormats, her forced frolics and simpering are as uncomfortable for us to watch as for her to perform.
But Diaz has no problem trotting out her aggravating giddy-girly act, jabbering and bounding around like an over-caffeinated seven-year-old.
Romcom specialist Nancy Meyers' previous endeavour was the far superior Something's Gotta Give; a title better suited to this patience-trying ordeal.
Grindingly predictable and sickeningly convenient, it's as false as a plastic tree.