INSIDE LLEWYN DAVIS (R) The Coen brothers, Joel and Ethan, have made several exceptional movies in their long career—Miller's Crossing, Barton Fink, Fargo and No Country for Old Men. But their latest might just be their finest. Set mostly in New York City in 1961, Inside Llewyn Davis focuses on a struggling folk musician, played by Oscar Isaac, trying to make it in the flourishing music scene of hip Greenwich Village coffee houses and nightclubs. Llewyn is not a performer without talent. He's able to land plentiful live gigs and the occasional recording session, but he's perpetually broke and relying on the frustrated good graces of rich Upper West Side friends, the Gorfeins (Ethan Phillips and Robin Bartlett), and a spurned lover and fellow musician, Jean (Carey Mulligan), to help nudge him through life. And that's the crux of Llewyn's dilemma: He's not the master of his own destiny. He's adrift in his own existence and floundering—not exactly a failure, but he's indeed failing. 

The Coens have long offered up male protagonists on the skids. Llewyn may be their most complex and troubling character yet, though he is always brutally recognizable and sympathetic. But he's also frustrating in how he deals with other people and selfish to those who love him the most. For an artist who trades in heartfelt songs about emotions and real human connections, Llewyn is one tone-deaf dolt. Llewyn's interactions with Jean are painfully awkward and insensitive, as are his engagements with several strangers and acquaintances. His forced relationship with the Gorfeins' cat, however, highlights his underlying sensitivity, although it simultaneously reveals his mixed-up priorities. Isaac delivers one of the most understated and affecting performances of the year, displaying a brutal, subtle disregard in his eyes at one moment, yet revealing increments of pain, bewilderment and frustration in his facial expressions the next. It's a breakout performance. 

This is a masterfully realized movie, entirely character-driven, though always dramatically engaging and emotionally rich. The Coens' penchant for dark humor and absurdity is still ever-present, though Llewyn's sometimes painful journey is never chronicled without warmth, despite the movie's wintry look. It's also one of the finest, most perceptive movies about artistic failure ever made. What happens to the performer good enough to draw a crowd, but not great enough to become Bob Dylan? In a year of great movies, this is my pick for best of 2013.