For nearly four decades, the phrase “Rush fan” has served as shorthand for a certain type, or stereotype, of male: suburban, well read in science fiction and the works of Ayn Rand, maladroit at interpersonal exchanges with women, immune to embarrassment when it comes time for a public display of air-guitar skills. In Rush: Beyond the Lighted Stage, a documentary about the venerable rock trio, the filmmakers Scot McFadyen and Sam Dunn explore how three amiable and seemingly bland fellows from Canada, nerdy suburbanites themselves, accumulated so many fans to become what Geddy Lee, bassist and lead singer, wryly describes as “the world’s most popular cult band.”

The film is filled with insightful interviews with the consistently charming and thoughtful members: Lee, Alex Lifeson (guitarist) and Neil Peart (drummer). But Lee himself warns the filmmakers: “Don’t be surprised to discover how boring we really are.” And, really, if it weren’t for Peart’s struggles with personal tragedy and his brief soul-searching sabbatical from the band, the movie wouldn’t have much of a story arc.

Then again, for Rush fans, story arc isn’t the point. The point is to appreciate the music—that heady (pretentious, according to detractors) mix of intense dynamics, shifting time signatures and visceral instrumental virtuosity. Though this film is fun to watch—it offers a wonderful overview of the band’s various hapless attempts at creating an image: from flowing robes and handlebar moustaches, to Miami Vice suits and beaver- pelt mullets—and is well put together with excellent concert footage, as a documentary it ultimately, and inevitably, falls short of its goal.

As a recovering Rush fan myself (prone to the occasional exultant relapse) I would say the goal is unachievable—there is no answer to the question, what is it about Rush? It’s like the old Louis Armstrong koan: “If you have to ask what jazz is, you’ll never know.” Consequently, Beyond the Lighted Stage is probably a fans-only documentary.

But when you consider that the group ranks third for most consecutive gold or platinum studio albums (after the Beatles and the Stones), the filmmakers need not worry about attracting enough viewers, air guitarists every one of them.