For film buffs, the arrival of a new Coen brothers picture is always cause for celebration -- but the first trailer for the critically lauded filmmaking duo's new release, 'Inside Llewyn Davis,' also includes something of note for classic rock fans.

We're talking, of course, about its inclusion of 'Farewell,' a somewhat obscure Bob Dylan song originally recorded -- and discarded -- during the sessions for 1964's 'The Times They Are a-Changin'.' After laying dormant for decades, 'Forever' was formally released on the 2010 vault-purging collection 'The Bootleg Series Vol. 9 – The Witmark Demos: 1962–1964.' Clearly, someone in the Coen camp is a Dylan completist, because a version of the track (apparently different from the one included in 'The Witmark Demos') forms the musical foundation for the 'Llewyn' trailer.

The choice of 'Farewell' makes sense, given that 'Inside Llewyn Davis' is a fictionalized retelling of the life and times of legendary Greenwich Village folk artist Dave Van Ronk, whose substantial talent and indelible identification with the neighborhood earned him the nickname 'The Mayor of MacDougal Street.' While Oscar Isaac, who plays Davis in the film, reportedly does a fair amount of his own singing and playing, it wouldn't be a Coen brothers movie without an eclectic, impeccably sequenced soundtrack -- and it looks like the 'Llewyn Davis' disc will feature a few minutes of vintage Dylan. Check out the trailer below.

Watch the 'Inside Llewyn Davis' Trailer

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