Folk music is supposed to be the music of the people. Yet at the heart of Joel and Ethan Coen's Inside Llewyn Davis, set in New York in the winter of 1961, is a folksinger with no feeling for people. The Llewyn Davis of the title, played by Oscar Isaac, is a broke, rumpled moocher who drifts from couch to couch until there are no couches left — either by drinking too much and getting rude or simply by opening his mouth to let his hostile thoughts flow out, he has a talent for alienating every friend he's got. He's also a gifted singer, but the material he chooses leans toward traditional weepers about mourning dead lovers. If Llewyn had a bell, he most definitely would not ring it in the morning; he'd be too hungover, or at least just too pissed off at the world. Llewyn is in many ways a dreadful human being, but you can't turn away from him — he's devastatingly handsome in a Sephardic way, the kind of damaged goods some women can't help falling for. The Coens seem to love him, too: Inside Llewyn Davis is the warmest picture they've ever made, and it's possibly their best. Taking place over just a few days, it evokes a fleeting time, place, and vibe: The Village folk scene of the early 1960s. That pre-Dylan world, the setting for Inside Llewyn Davis, may be very small, but Llewyn is lost in it. Although the Coens are consummate craftsmen, they don't always show the lightness of touch, or the depth of feeling, they do here. It's cockeyed humanism at its best.