A romantic comedy, it has often been observed, needs an obstacle, a force of natural confusion to keep its objects of affection (temporarily) apart. On the other hand, there’s Love Actually, the first movie directed, as well as written, by the compulsive British crowd-pleaser Richard Curtis (”Four Weddings and a Funeral,” ”Notting Hill”). Set in London during the weeks before Christmas, it’s a toasty, star-packed ensemble comedy in which a handful of lonelyhearts attempt, with some success, to come out of their shells, and it’s going to make a lot of holiday romantics feel very, very good; watching it, I felt cozy and charmed myself.

It’s worth noting, however, that the appeal of ”Love Actually,” a movie as sweetly munchable as a Christmas cookie (and about as nourishing), lies in the way that its romantic ”obstacles” are, for the most part, barely even there. Curtis’ cheaply winsome stroke of genius is to have made an unabashed celebration of the fairy-tale obvious — that love is standing right in front of you, and that all you need to do is reach out and grab it. Your average Jennifer Aniston or Luke Wilson character should only have it this easy.

At the beginning, Bill Nighy, looking like a trampy, gone-to-seed Crocodile Dundee, appears in a recording studio as a raunchy has-been rock star who’s gotten corralled into doing a special yuletide version of ”Love Is All Around.” He thinks the song is crap, but, make no mistake, it will stick in your head (for days), and the rest of the movie follows suit: It’s fashionably acerbic about being unfashionably sappy. We’re soon introduced to Hugh Grant as the newly elected prime minister, and before we’ve had a chance to giggle at the amusing perfection of Grant, with his elegant downcast features, playing an alpha-male bachelor version of Tony Blair, he has fallen head over cuff links for his new personal assistant (Martine McCutcheon), whose radiant moon face reflects that affection back at him.

It just wouldn’t do, of course, for the freshman PM to be shagging his servant. So Grant flirts with her in innocent, stammering agony. He has become a peerless romantic star, even if the film takes a bit too much delight in having him shimmy around the mansion to the Pointer Sisters’ ”Jump,” as though to prove that British men can be funky too. If anything, this particular PM should probably be listening to Billy Joel’s ”Tell Her About It.”

In a bizarre retrograde twist, ”Love Actually” is preoccupied with liaisons between shy, chivalrous male bosses and pliant female underlings. In addition to Grant, there’s Colin Firth as a cuckolded novelist who finds the perfect companion in his willowy Portuguese maid (Lucia Moniz), who doesn’t quite speak English. Meanwhile, Alan Rickman, as a somber executive stuck in a comfy marriage to a touchingly devoted Emma Thompson, must fend off the advances of his sex-bomb secretary (Heike Makatsch). He seems to be doing a fair job of it until he decides to buy the assistant a gold necklace. Thompson’s reaction upon discovery of this secret Christmas gift is the film’s most wrenching moment, though the episode would be stronger if we had any idea what was going on in Rickman’s head. The gravity of it all is balanced by the levity of two professional movie stand-ins who chat politely as they mime sex, nude, all day long, and also by a goofy-faced bloke (Kris Marshall) who thinks that his English accent will make him a stud in America. (In the film’s cheesiest gag, he’s proved right.)

Meanwhile, Laura Linney, with those dimples you just want to curl up in, is adorable as a pathologically shy American with a consuming crush on her office colleague (Rodrigo Santoro). After working up the nerve to take him home, Linney has one of those exhibitionistically private, hands-in-the-air ”Yes!” moments that’s meant to unite the audience in vicarious happiness. But the joy, rather inexplicably, is short-lived, as it turns out that she’s too wrapped up in caring for her mentally ill brother to let herself go. Ultimately, a more compelling case of amorous denial arrives with the blithely charismatic Andrew Lincoln as a fellow who’s doing all he can to hide his secret yearning for his best friend’s wife (Keira Knightley). If that doesn’t pluck your heartstrings of bittersweet nobility, try Liam Neeson as a widower who coaches his 11-year-old stepson (Thomas Sangster) into confessing his feelings to the girl he has a crush on.

Tell her about it, indeed. At its best, the movie reminds you how one such moment can activate, and set, your lifelong romantic compass. That’s ”Love Actually”: the heartfelt, sometimes the wise, layered atop the unfinished and the glib, with even the British prime minister as just one more sweet and lonely guy who’s really got to get out of the house more.