Grateful Dead's Bob Weir performing at Sundance for upcoming film 'The Music Never Stopped' -- EXCLUSIVE VIDEO

Image Credit: Fred Hayes/Getty ImagesDeadheads at this year’s Sundance Film Festival got a treat when Grateful Dead founding member Bob Weir showed up with a mic and an acoustic guitar to performing a collection of Grateful favorites, including “The Music Never Stopped,” to support director Jim Kohlberg’s upcoming film of the same name, slated for release March 18 and starring J.K. Simmons (The Spiderman movies, Juno) and Lou Taylor Pucci (Thumbsucker). Watch below:

The Dead, seminal ‘60s rock group and jam-band trailblazers, feature heavily in the film’s soundtrack and story, as does the music of Bob Dylan, Buffalo Springfield, The Beatles, Crosby, Stills, Nash & Young and The Rolling Stones.

Set in the ‘80s and based on a book by famed neurologist and author Oliver Sacks, the film follows engineer Henry (Simmons) as he reunites with his erstwhile runaway son, Gabriel (Pucci). The rocky relationship is strained when a brain tumor renders Gabriel unable to form new memories and mentally strands him in the late ‘60s.

Henry begins exploring music therapy to reconnect with his son, finding that Gabriel responds favorably to the work of Dylan, the Dead and other hippie-era mainstays. Though Henry hates the genre (especially since forbidding Gabriel to attend a Grateful Dead concert is what prompted Gabriel to run away in the first place), he knows it’s his son’s only hope.

Weir’s Sundance set also included Dead staples “Truckin’,” “Jack Straw” and “The Other One.” The intimate show took place at the ASCAP Music Café in Park City, Utah.

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