If you had gone to see "Inside Llewyn Davis" expecting something along the lines of "O Brother, Where Art Thou?", you would have soon been somewhat perplexed. Notwithstanding its musical substructure, this is not that kind of Coen Brothers film. Rather, it's another of their somewhat abstracted time-and-place-rooted character studies, along the lines of "The Man Who Wasn't There" and "A Serious Man" (and, let's suggest, "Barton Fink" -- you could probably add "No Country For Old Men" in there, too, although it bleeds heavily into another type of Coen Brothers film entirely): character studies in which the leading character is not particularly likeable, or charismatic, or even interesting, and in which therefore the life of the film occurs in the characters and situations that the leading character walks through (or into) or bounces off. And those characters and situations, this being the Coen Brothers and all, are exceedingly rich. (Two words: John Goodman.)
The early 1960s Greenwich Village folk scene plays the role that late 1960s Jewish Minnesota played in "A Serious Man". It's a fascinating world to be sucked into, with its curious mixture of idealism, opportunism, hucksterism, patronage and abject poverty. Underneath it all is the music: "traditional" folk music circa 1960 isn't something I generally turn to for pleasure -- it seems too earnest, colourless and worthy in the light of what Bob Dylan (who "appears", inevitably, at the end of this film) was soon to do to it -- but there is a lot to enjoy about it here, not least Oscar Isaac's golden voice.
But the best part of the film for me, musically speaking, comes during the closing credits, when we get Dave Van Ronk playing and rasping his way, exquisitely, through "Green, Green Rocky Road" (a song which Oscar Isaac turns his hand to earlier in the film, as if to further cement the already fairly firm connection between the fictional Llewyn Davis and the real-life Van Ronk (the existence of this album, and the prominent appearance of a cat on its cover, are not likely to be coincidences)).