The true test of a biographical documentary is whether it is only of interest to those with a previous inclination towards the subject. Joan Rivers: A Piece of Work, for example, is skillfully made and compelling, yes, but it is also a show-biz doc full of recognizable faces, focused on a personality who has (for better or worse) been a part of public life for decades. But the question is: would we still enjoy the documentary if we knew absolutely nothing about Rivers or any of the names the picture drops?

The opportunity to put this theory to the test has finally risen, for this reviewer anyway, with Strange Powers: Stephin Merritt and the Magnetic Fields, Kerthy Fix and Gail O'Hara's portrait of the indie pop band and their raconteurish frontman/songwriter. And though the Fields are the type of group that we semi-hip thirtysomething New York writers are supposed to be in tune with, their music was a total mystery to me until the film unspooled.

The band has been together since 1989, and is iconic to some but, according to the film, unknown to most (okay, so I don't feel so bad). There is some biography and performance footage, but for the most part, the film is a portrait of an artist at work--and it plays best on that level. We see Merritt at work in his tiny New York studio apartment, finding odd instruments and laying down pieces of songs with his longtime collaborator and manager Claudia Gonson. It's an eccentric working environment ("I have outgrown my mallet box"), a small room presumably made more cramped by the duo's occasionally testy working environment. "Claudia and I argue several times a day," Merritt confesses, and the camera catches a few of those confrontations, which escalate and explode as quickly and evenly as they deflate.

Throughout the film, the dynamics of the band--how they interact with and respond to Merritt's prickly personality--provide a fascinating subtext to their formation, development, and current niche success. Soft-spoken and often funny, Merritt is a dauntingly intelligent, fascinating guy, and as the film progresses, it is clearly and cleverly imbued with his dry wit. But the filmmakers also respect--in fact, they seem in awe of--his tireless work ethic, both now and in his early struggle for a style and a voice (and an audience). He is seen showing off his instruments, going through his CD collection, thumbing through his old notebooks, which include proclamations both large (his "forumlist manifesto") and incidental. But even the small ones can grow into something huge, as with his "100 Love Songs" project (we see the scribble in close-up: "I hereby swear to do this")--later whittled down to an apparently more manageable 69 tunes for the group's successful 69 Love Songs set.

As filmmakers, Fix and O'Hara occasionally come up short in their quest to penetrate the wall of Merritt's aloof personality; we get a sense of who he is, but we'd like more of an understanding of why he's that way (particularly in an awkward but hilarious clip of him on an Atlanta morning show). And the section that deals with the controversy over his views on black music is tantalizing, but frustratingly brief.

So, as psychology, Strange Powers is hit and miss. But as fly-on-the-wall documentary, it's intriguing stuff--we see the group working on their eighth album, building a song track by track, taking the album out on tour, and continuing to work from long distance after Stephen moves to L.A. There aren't a lot of music documentaries that feel genuine, that they're really capturing the day-to-day logistics of being in a band and creating work. Strange Powers does that, and does it very, very well.

Jason lives in New York. He holds an MA in Cultural Reporting and Criticism from NYU.