Mexican filmmaker Alfonso Arau, who was introduced to American moviegoers with the popular "Like Water for Chocolate," tries to recapture that film's sense of magic and romanticism in his first American effort, "A Walk in the Clouds." But while his style is in full bloom, the film lacks substance.

Arau is at his best filling the screen with memorable visual imagery, but he needs a stronger script than this silly soap opera provides. In fact, it might have worked better as a comedy — and it certainly could have used a more charismatic leading man.

As Paul Sutton, a naive American soldier who stumbles into the lives of a vibrant Mexican family that owns a large winery in California's gorgeous Napa Valley, Keanu Reeves is at his most bland. A certain understatedness seems natural for the character, but Reeves' flat line readings undermine the lush, unabashedly romantic dialogue.

The film begins as Paul returns home from World War II to find that he has nothing in common with his young cutie-pie wife Betty (Debra Messing), whom he impulsively married before shipping overseas. Haunted by wartime nightmares laced with personal angst, Paul just wants to pursue the American dream — home and hearth, children and a dog, etc.

When he hits the road to find himself he instead finds Victoria Aragon (Aitana Sanchez-Gijon), a college student on her way home to "The Clouds," a nickname for the family winery. She looks forward to seeing her supportive mother and grandparents, but is worried about facing her bombastic, intolerant father (Giancarlo Giannini), as she is pregnant and unmarried.

So, Paul offers to be her husband for a day or two, a ploy that is, of course, doomed to failure. And there's no doubt from their first meeting that Paul and Victoria will gradually fall in love.

Arau fills the screen with vivid colors and heavenly images, using the harvesting of grapes as a metaphor. (A grape-stomping sequence is particularly sensuous.) And there are a number of individual moments that are quite entrancing (enhanced by Maurice Jarre's lush music), despite the feeling that it's all a bit empty.

The intent here is to achieve an old-fashioned Hollywood feeling of the period. This is postwar America as filtered through old movies, and the initial scenes of Paul coming to realize his marriage to Betty is a mistake could be Dana Andrews and Virginia Mayo in "The Best Years of Our Lives."

In the family scenes, it is Anthony Quinn as the grandfather who steals the show with a hilarious and touching performance as the sage old voice of dubious wisdom. Everyone else in the cast is equally lively, however, with Sanchez-Gijon managing to combine an unlikely sense of both innocence and sensuousness, while Giannini is charmingly hammy.

Unfortunately, it is the contrast that makes Reeves' performance seem all the more lacking. He's earnest, but the film needs something more.

"A Walk in the Clouds" is rated PG-13 for wartime violence (in flashbacks) and a raging fire in the fields, as well as one profanity and some sexuality.