Jeanne and the Perfect Guy is a French musical about a frisky woman (Virginie Ledoyen) with a panting horde of boyfriends. Her truest love turns out to be an HIV-positive heartthrob (Mathieu Demy, son of Agnes Varda and Jacques Demy). The filmmakers try for a bittersweet lyricism à la Jacques Demy’s The Umbrellas of Cherbourg but end up with something closer to his genial misfire The Young Girls of Rochefort. The movie’s combination of froth and political activism doesn’t gel, and the song-and-dance numbers never achieve liftoff, perhaps because nobody involved can sing or dance.