Coming to a Jack-n-Coke near you. LEMMY MOVIE LLC

If you sit down to watch Lemmy: 49% Motherf**ker, 51% Son of a Bitch—the new documentary about Lemmy Kilmister, the whiskey-guzzling, two-pack-a-day-smoking, Rickenbacker-bass-playing frontman of Motörhead—expecting a VH1 Behind the Music–style exposé, you'll be sorely disappointed, especially if you get a text that says, "My friend's sister once snorted a line of coke off Lemmy's cock!!!" 10 minutes in. Debauchery is a staple of metalhead memoir, thanks to efforts like Mötley Crüe's 2001 autobiography The Dirt or that Behind the Music episode where Ozzy Osbourne admits to being so fucked-up he snorted ants off a sidewalk.

Instead, filmmakers Greg Olliver and Wes Orshoski follow Lemmy for more than three years, recording tour footage and candid at-home interviews. This approach renders Lemmy a surprisingly human story, one of a man who's not only been a notoriously hard-livin' rocker for almost 50 years (he joined his first band, the Rockin' Vicars, in 1965), but also very much a humble man, and the rad dad you wished you had.

Born Ian Fraser Kilmister on Christmas Eve in 1945, Lemmy grew up without a father ("[He was] a miserable little dickhead... All he ever did was walk out on me"), but he seems determined not to follow suit. In another interview, the filmmakers ask what's the most treasured possession in his cluttered apartment. "He is," he says, pointing to his son—awfully sweet for the subject of a movie with the tagline 49% Motherf**ker, 51% Son of a Bitch. (He later tells his son, "Promise me you won't do coke. Do speed, it's better for you.")

When not on tour, Lemmy lives in a tiny two-bedroom near the Sunset Strip in Los Angeles because "the rent's only $900 a month" and it's close to the Rainbow—where he holds court, almost daily, in front of the video poker machine, drinking Jack-n-Cokes, signing autographs, and telling bad jokes ("How do you make a dead baby float? Two scoops of ice cream, two scoops of dead baby!").

In what's sure to be one of the most controversial scenes in the film, Lemmy shows off his collection of knives, swords, and uniforms—a room filled, floor to ceiling, with Nazi memorabilia. Afterward, he explains away any potential accusations, stating—so earnestly it's hard not to believe him—that he's had "five black girlfriends, and that'd surely make [him] a really bad Nazi."

The film's primary fault is that both the filmmakers and the long list of interviewees—including Alice Cooper, Joan Jett, Slash, Metallica, Ozzy, Jarvis Cocker, and Ice-T—are such überfans of Motörhead that the whole thing slips into gushy, geeky hero worship. No one has a bad thing to say, except maybe his second band, Hawkwind (the "prog-rock band that punks liked"), which Lemmy was fired from after being arrested at the Canadian border for amphetamine possession.

But it was Lemmy's need for speed that gave birth to Motörhead in 1975. "I remember the time before rock 'n' roll. All we had was Rosemary Clooney records. Then suddenly Little Richard came along. It changed everything." Motörhead also changed everything. They pretty much invented heavy metal, rivaling Black Sabbath. "If they'd said to me, 'Who would you say was the original metal band?' it was a toss between Lemmy and Black Sabbath—but I would say Motörhead," says Ozzy in one scene. Motörhead's sound—"speed freaks playing speed music"—also gave birth to the more specific genre of thrash metal. Without them, we'd have no Metallica, no Anthrax, and no Slayer.

Maybe Lemmy's unflinching straightforwardness was the reason filmmakers were hard-pressed to get anyone to talk smack about the Kill-Meister—the undisputed Godfather of Metal. He's honest and unapologetic. He never married and continues to live a life of touring, drinking, and drugging—and refuses to brag about it. "I don't want kids to take drugs 'cause of me. I also wouldn't tell them to stay off of drugs, but I don't want to advertise the lifestyle that killed a lot of my friends." Somehow surviving himself, in 2011, Lemmy is still unstoppable—a 65-year-old with high blood pressure, diabetes, and 35 years of Motörhead under his bullet belt. In the last minutes of Lemmy, the interviewer asks what keeps him going. "You have a dream when you're a kid. And my dream came true," he says. "So why ever stop?" recommended