"One Day" won't set the world on fire but it radiates pleasing warmth. The story line -- virtuous working-class girl tames wealthy charmer -- has been reliably jerking hearts since Jane Austen was in diapers. The characters are a bit more complex and believable than the mannequins usually found in romantic comedy-drama, and the European locations are nearly as eye-catching as the lead actors.

Emma (Anne Hathaway) and Dexter (Jim Sturgess) begin their relationship on the day they ought to be parting. Following their college graduation on July 15, 1988, the virtual strangers tumble into Emma's bed. Their less-than-perfect union would have Bridget Jones cringing in embarrassment, but the pair laugh off their initial encounter and become unlikely friends.

The film, based on a bestselling book by David Nicholls, follows them by observing anniversaries of their meeting over the course of more than 20 years. If you've seen "The Way We Were" or "Same Time, Next Year," you know the drill. Sunrise, sunset, disconnecting, reconnecting, laughter, tears, babies.

But Nicholls' screenplay and the direction by Lone ("An Education") Scherfig respect our intelligence. The opening scene of graduation-night carousing in Edinburgh implies a lot without any clumsy exposition. Hardworking Emma has bootstrapped her way up to a midlevel university, while Dex, the ladies' man and bon vivant, fell short of the prestigious schools his peers are attending.

While Anne Hathaway can coast through a film on her saucer-eyed stare and kilowatt smile, she makes Emma more than a collection of tricks and tics. She's proud yet easily wounded. Her hangdog expression while waitressing in a downscale Mexican restaurant is eloquent about her foiled expectations. A would-be writer in a straw sombrero passing out menus is not a happy sight. She's bright, charming and dedicated to her dream career as an author, yet her wavering confidence and propensity for sarcastic wit humanize her. There's enough drama in the part to pave Hathaway's path to roles beyond romcom It Girl.

The chick-flick algorithm dictates that whatever level of fame the star occupies, the male lead must be at least one step down. Sturgess (second-billed in "Across the Universe," which no one saw) is not a bad actor but he's light on personal magnetism. As Emma's deeply flawed crush, he spirals downward from his upper-class origins, hosting a tacky TV variety show and soothing his ego with drugs, alcohol and unseemly women. It's puzzling why the pair's attraction remains so fondly steadfast through their many romantic near-misses, shouldas, couldas and wouldas. That's why it's called fiction, I guess.

Over the years Emma grows sophisticated, trading her girlish sundresses and clompy boots for heels and couture, while life-battered Dex comes to appreciate good old Emma as more than a source of sympathy. The film doesn't end with a happily-ever-after fadeout but a tougher, emotionally satisfying resolution. "One Day" is a winning late-summer flight of fancy with a good lesson about making amends for one's misused life opportunities.