There's one good reason to see this biopic of the French pop-cabaret songster Serge Gainsbourg, and that's its lead actor, Erik Elmosnino. He's not just a dead ringer for Gainsbourg (which is to say, he looks like a deeply serious elf with a touch of Nosferatu), he nails his sexy, disheveled poetic machismo. But Gainsbourg: A Heroic Life is at once overly episodic and playfully arty, like a TV movie made by Fellini. B–

