Sometimes, a film hits on an idea so good that failure practically takes a conscious effort. Like a remake of Planet Of The Apes in which the apes and the leading man attempt to out-dull one another, the Spanish import The Other Side Of The Bed takes a winning idea and drives it directly into the ground. Set amid the love-addled young cosmopolitans of Madrid, the film begins with hangdog Guillermo Toledo getting his walking papers from free-spirited girlfriend Natalia Verbeke. He takes solace in the friendship of his best friends Ernesto Alterio and Paz Vega, little suspecting that Verbeke has taken up with Alterio, or that Vega might be developing her own romantic designs. (Apparently, Madrid forbids residents from dating outside a radius of four city blocks.) The film, by director Emilio Martínez Lázaro and writer David Serrano, might have been a standard tale of bed-swapping among impossibly photogenic actors, if not for a twist: It's a musical, with song-and-dance numbers erupting in such mundane locations as office buildings and gym bathrooms. And it might have worked, if it weren't for a counter-twist: The singing, songcraft, and choreography all suggest a hastily executed junior-high play. Doled out between long stretches of talky relationship hand-wringing and elementary farce, the songs drown traditional musical numbers in Euro-pop pudding, with the visibly uncomfortable cast warbling its way through literal-minded (or at least badly translated) lyrics, as out-of-sync chorus dancers busy themselves behind the leads. It might all somehow be for effect, but it's difficult to think what effect that might be, apart from embarrassing actors and audience alike. Then again, The Other Side Of The Bed became a hit when it played Spain last year, so maybe certain tastes just don't make it across the Atlantic, or the rest of the world is behind the curve. Maybe wretched singing and fumbly dancing will soon surpass craft and skill.