"Long Strange Trip" is an epic documentary about the Grateful Dead that was 14 years in the making.

The film, directed by Amir Bar-Lev, explores the Bay Area's most famous band while staying accessible to casual fans and even non-fans. "There are very few people who are indifferent to the Grateful Dead," Bar-Lev said on "Salon Talks." His labor-of-love film, which was executive produced by Martin Scorsese, is the first full-length film made about the polarizing American band and it chronicles in spectacular detail the 30 years the performers spent together.

The publicity-averse music group, which was famously led by the late Jerry Garcia, eschewed typical fame and became tremendously successful in spite of its inability to produce music that would sell widely through typical music industry channels, like radio. The Dead became one of the highest-grossing concert acts in America, drawing on word-of-mouth among its scores of followers.

"Those of us who are fans are notoriously bad at explaining what's so great about our favorite band, and that's because it's an experiential thing," noted Bar-Lev. "It's not impossible to describe [like] food or music or sex, but it's something like 'you gotta check it out yourself!' So I was aware that there was a gulf between people who love the band and people who were kind of turned off by the inarticulateness of most of us" who find the band's allure hard to explain, he added.

Watch the clip above to hear Bar-Lev talk about exploring counter and subculture that continues to surround the legacy of the Dead to this day.