"The Runaways" is a rock movie that gets so many things right, you want to forgive its awkward structure. The picture tells the wild-ride story of the all-girl band whose music, over the course of a three-year recording career in the mid-1970s, met with radio incomprehension in this country, but won fans abroad and set a template for the female rock groups that would follow. The film is based on "Neon Angel," a quick-read memoir by Runaways singer Cherie Currie. This is the awkward part. Currie's evolution from a 15-year-old Bowie fan with a screwed-up family to a jailbait icon with a screwed-up head (drugs, booze, the usual) provides the movie's emotional center; but the story's natural focus should logically be Joan Jett, the band's darkly compelling guitarist and most productive songwriter. Turning her into a supporting character throws the film off.

Still, more than any movie since "Almost Famous," "The Runaways" captures the intoxicating power of rock-and-roll music to transform young lives — to lift teenage nobodies up into the clouds of stardom (and then, more often than not, dump them back down into the real world they had dreamed of escaping). The director, Floria Sigismondi, a music-video veteran making her first feature, has admirably refrained from shooting the picture like a music video; and she doesn't exploit the story's lesbian motif for cheap thrills. She's also been fortunate in casting her lead actors — it's hard to imagine how Dakota Fanning (as Currie), Kristen Stewart (as Jett) and Michael Shannon (as the band's raving, madman manager, Kim Fowley) could be any better in their roles.

The Runaways weren't the first all-girl band — Goldie and the Gingerbreads had major-label singles in the '60s (and opened for the Rolling Stones), and Fanny released well-regarded major-label albums in the early '70s (big fan: David Bowie). But the Runaways had the times on their side, coming together in late 1975, just as punk rock was welling up in New York City. They were never exactly punk-rockers themselves (their sturdy guitar riffs derived from an earlier hard-rock style); but in their pugnacious attitude, they happily affiliated with the new loud-and-fast musical movement.

The picture begins with a startling sequence involving Cherie and her twin sister, Marie (Riley Keough), and a drop of blood on a patch of gravel. The girls' dead-end lives are quickly sketched in — absent mom, alcoholic dad — and we see Cherie's disastrous lip-synching performance at a high-school talent show. Joan Jett, meanwhile, is shopping in the men's section of a clothing store, where she picks up a vintage black-leather jacket. Joan is only beginning to learn guitar, but she wants to start an all-girl band. One night, outside an under-21 club, she spots Kim Fowley, a thirty-something creep wearing a dog collar and proclaiming, "I am the king of hysteria himself!" (Shannon leaps into this character as if it were the title role in an old-time monster movie.) Joan broaches her band idea and Fowley immediately sees its possibilities. In the movie's version of the story, Fowley — a legendary producer, songwriter and music-biz hustler whose career dates back to the early '60s — introduces Joan to a drummer named Sandy West (Stella Maeve). Then, on the prowl for a singer one night, Joan and Fowley spot Cherie at the same club, Joan giving her an appreciative once-over and Fowley telling the new kid, "We love your look, and we are choosing you to be a part of rock-and-roll history." He doesn't much care if she can actually sing.

By now a hot guitarist named Lita Ford (Scout Taylor-Compton) and the first of several Runaways bassists have been recruited, and the harshly abrasive Fowley begins putting the band through rock-and-roll boot camp. (He even brings in a group of guys to one of their rehearsals to hurl bottles at them — a warm-up for the hostility he promises they'll encounter as an all-girl group setting sail on a sea of hard-rock testosterone.) Joan lives for the music, but Fowley is all about titillation: "This isn't women's lib, kiddies — this is women's libido!" He keeps their stagewear tight and skimpy; puts them out on the road, where they struggle and starve; then gets them signed to Mercury Records — the big time. However, despite such memorable tracks as "Dead End Justice" and the classic "Cherry Bomb," their first album fails to sell (as does its follow-up, Queens of Noise). But overseas — and especially in Japan — the Runaways are stars. Flying to Tokyo, they're met by herds of screaming fans — Runaways mania. Unfortunately, the group is already starting to fall apart.

Fanning and Stewart do their own singing here (Stewart took guitar lessons, too), and they're really good — songs like "I Love Playin' With Fire" and "I Wanna Be Where the Boys Are" are as rousing as the original Runaways tracks. Fanning has nailed down the perfect lost-angel presence for her portrayal of Cherie (compare it with old Runaways concert footage and you can see how close she's come to the original model); and while Stewart spends a lot of time slightly off to the side, she makes herself felt in every sequence in which she figures. Her ambiguity — as a friend, as a lover — is fascinating, especially in a scene in which Joan is lying on top of Cherie, breathing pot smoke into her mouth, and the camera looks up into her dark, otherworldly eyes, wondering what she's wondering, and what she sees coming.

The picture's conclusion is unusually moving. Very few words are said, but in showing us a woman who won't stop following her dream and another woman who can't come along, it says everything.

Don't miss Kurt Loder's reviews of "Repo Men" and "The Girl With the Dragon Tattoo," also new in theaters this week.

Check out everything we've got on "The Runaways."

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