Lovable losers abound in the films of Joel and Ethan Coen. Even the most ardent admirer of Raising Arizona's H.I. McDunnough or The Big Lebowski's the Dude would be hard-pressed to call either man conventionally successful. But that's kind of the point: The old adage about loving someone for his flaws holds true in these cases. Keep that in mind when you meet the title character of Inside Llewyn Davis. A down-on-his-luck folk musician in 1961 New York City, Llewyn (Oscar Isaac) crashes on friends' squeaky couches, gigs at the Gaslight Cafe and mills about while waiting for his big break. It isn't much of a spoiler to say he'll be waiting awhile. Llewyn himself seems aware of this, questioning whether to keep chasing fame or to admit defeat and re-enlist in the Merchant Marine.

Witnessing all this unfold is, in a word, lovely. That may seem an odd way to describe such a bittersweet portrait of failure and disenchantment, but the Coens are experts in drawing out the bitter and the sweet in nearly equal measure. Inside Llewyn Davis continues in the sincere, unironic register established (surprisingly, to some) by their 2010 remake of True Grit. But that's not to say it lacks their signature black humor. At one point, Llewyn tells a fellow musician played by John Goodman that his former musical partner "threw himself off the George Washington Bridge." Goodman wryly responds: "You throw yourself off the Brooklyn Bridge, traditionally. George Washington Bridge—who does that?"

Goodman's role is essentially an extended cameo, as is that of Justin Timberlake, who plays yet another struggling musician. Colorful characters pop up here and there, as they do in all the Coens' movies, but Inside Llewyn Davis is ultimately a one-man act. We follow Llewyn almost painfully closely as he tries to improve his lot, or at least make sense of it, and we root for him as we would a home team down by a point in the fourth quarter. All the while, Bruno Delbonnel's soft-focus cinematography makes his fumblings seem even more desperate.

Llewyn eventually sees the words "What are you doing?" written on a restroom stall, and he seems genuinely taken aback. As the viewer, getting to share in Llewyn's struggle to answer that question in any meaningful way is more than worth the accompanying sorrow.

Critic's Grade: B+

SEE IT: Inside Llewyn Davis is rated R. It opens Friday at Fox Tower.