“Lemmy is the baddest motherfucker in the world,” exclaims Dave Grohl in this fawning new music doc. It’s a sentiment shared by almost everyone who appears on camera, including Dave Navarro, Ozzy, Metallica, Slash, and Billy Bob Thornton. Devotees of Motörhead frontman/certifiable rock icon Lemmy Kilmister will be in heaven watching this gushing love letter to the man who straddles rock subgenres, but anyone who’s not already a fan will cry for mercy long before the nearly two-hour film ends. Co-directors Greg Olliver and Wes Orshoski shot their film through a fanboy filter, sans any real critical (in the truest sense of the word) thought or evaluation. That carries Lemmy for a while as it meanders through his professional highs and lows and his personal life (Dad was a prick who deserted the family when Lemmy was a boy; the death of a girlfriend when he was a teenager is presented as his “Rosebud,” explaining everything from his choice of drugs to his arm’s-length treatment of women). But Olliver and Orshoski are so enamored of their subject that they don’t whittle the fat from the meat. While there’s lots of humor and occasional insight, most scenes drag on long after a point has been made (or not made, as when softball questions are tossed about Lemmy’s affinity for Nazi memorabilia). The directing duo is too earnest to play with presentation when they stumble onto irony—such as when a surgically overhauled Joan Jett says of Lemmy, “He’s a renegade. Everybody else assimilates.”

(See more info on Kilmister here.)