Five coins in the fountain, which one will the fountain bless?

Attractive girl meets studly young guy, they show an easy, unforced chemistry and fall in love. A few of the jokes are even pretty funny. What could go wrong?

In the romantic comedy “When in Rome,” what goes wrong is the rest of the film. The standard romantic comedy part of the film is actually OK, if perhaps a little too standard. The problem comes from the twist. Two writers and a director, who possibly have never seen a movie before, thought it would be a good idea to interrupt this love story with an extended silly bit about a magic spell. The spell, alas, turns out to be the whole point of the film.

Kristen Bells stars as Beth, a curator at the Guggenheim Museum. She loves her job more than she has ever loved any man, which, considering her job, is understandable. Nevertheless, she is young and cute and therefore in want of a husband. No wonder she is peeved when her younger sister meets a guy, is engaged to him two weeks later and marries him three days after that (in a swank wedding that must have broken all records for being the fastest ever organized).

This wedding brings Beth to Rome as maid of honor, where she meets and falls for the best man, Nick, played by the interchangeable hunk Josh Duhamel. Beth is a klutz and so is Nick, and the repeated scenes of them breaking things or falling down grow quickly tiresome. But that doesn’t matter, because we soon are presented with the film’s major wrinkle. And we wish we weren’t.

In a tipsy pique, Beth pulls five coins out of one of the Roman fountains that grant wishes of love. This act makes the five men who originally threw in the coins fall instantly in love with her. For the rest of the movie, she is stalked in an unquestionably unfunny manner by the likes of Jon Heder, Will Arnett, Dax Shepherd and Danny DeVito.

Yes, Danny DeVito. Poor Danny DeVito. And it gets worse than that. He plays the owner of a sausage company, an occupation the filmmakers think hilarious. They make painful jokes about it, but their sense of humor is suspect. These are people, after all (writers David Diamond and David Weissman, and director Mark Steven Johnson), who think it is a good idea to have Beth pick five coins out of the fountain. Shockingly, they must not know the Comedy Rule of Three -- three variations on a theme are funny; five is overdoing it, especially when the jokes are this lame.

Fortunately, the movie has the excellent John Bailey as director of photography. Bailey (whose stellar work includes “Groundhog Day” and “American Gigolo”) makes Rome glow even more than it does already, and he makes New York sparkle.

So it looks great, and a good handful of the jokes shine (I like the part about the elevator best, but some will prefer the extended sequence inside an uber-hip Village restaurant). The main actors are appealing. And the beginning shows considerable promise.

All that is missing is a worthwhile story.