Photo: NBC Universal

Straightforward at the outset, the effervescent new comedy It's Complicated , in theaters December 25, more than lives up to its title. Jane (Meryl Streep) is a single mother of three with an empty nest, a smug-yet-charismatic former husband (with a lissome trophy wife), and well-meaning friends who ask, for instance, "Do you want to meet a guy on match.com I didn't like?" But all it takes to thicken the plot are a few drinks and a little architecture: Jane's boozy chance encounter with her ex (Alec Baldwin) leads to a secret affair; she's also getting flirty with the low-key recent divorcé (Baldwin's Oscars cohost, Steve Martin) who's remodeling her kitchen.

It would be hard not to adore any movie that puts Streep at the glowing center of a love triangle, but It's Complicated has more than just good taste in women. It hits wry, wistful notes about what-ifs and roads not taken, while also paying homage to classic screwball comedies (especially The Philadelphia Story ). The sight gags include Office cutie John Krasinski (as Jane's future son-in-law) looking fine in a set of ladies' pajamas (festooned with lipstick kisses, no less—thank you, costume department!) and a 21st-century version of the spicy love letter and the racy Polaroid: naked Skyping.

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