Based in part on the memoir "Neon Angel: The Cherie Currie Story," "The Runaways" is less a detail-oriented biopic of the first all-girl rock band and more a coming-of-age story where emotion takes precedence over comprehensive historical accuracy. There may yet be a more hard-hitting depiction of '70s teen group The Runaways, but that is not what this is, or needs to be. Writer-director Floria Sigismondi adeptly drops the viewer in a specific time and place, burrowing beneath the surface and finding the ambitious, somewhat broken souls of a young Joan Jett (Kristen Stewart) and Cherie Currie (Dakota Fanning). Costuming, hairstyles, production design, cinematography, music—Sigismondi gets the window dressing just right and then lets her two lead actresses run wild with juicy roles that get to the bottom of what it is like for young girls to be thrust into the limelight—and into dangerous, sexually-fraught boxes—becoming victims of hype, the media and their own immaturity before they have really had a chance to figure out who they are to themselves.

A few things 16-year-old Joan Jett does know is that she loves the electric guitar, lives to rock, and yearns for a future greater than her rough-and-tumble present. The time is 1975, and when she spots famed record producer Kim Fowley (Michael Shannon) outside a Los Angeles nightclub, she takes it upon herself to approach him and suggest something the world has never seen: a hard-rock band comprised wholly of female musicians. Sensing that Joan might be onto something, Kim introduces her to teen drummer Sandy West (Stella Maeve) and sends them off to start practicing. The rest of the group quickly forms, with Lita Ford (Scout Taylor-Compton) as lead guitarist and fictional composite Robin Robins (Alia Shawkat) on bass. The secret ingredient, however, turns out to be 15-year-old Cherie Currie, a blonde Brigitte Bardot type plucked from a club and made the bombshell lead singer. When The Runaways finally hit the road—and later sign a record deal—Cherie is thrilled to escape her broken family life at the expense of leaving twin sister Marie behind. As is so often the case, however, the money, fame and idolatry become too much, too fast, too soon, and before long the band is hanging by a thread as interpersonal discord and a hefty drug problem on Cherie's part spin things out of control.

The Runaways made their mark in history even as it all ended just as quickly as it started. In capturing this age-old conceit in a way that doesn't feel derivative, writer-director Floria Sigismondi imparts a loose, free-floating storytelling style to "The Runaways" that refuses to bog down in self-importance, overwrought melodrama, and point-A-to-point-B plotting. Instead, she gets right down to the innate feeling of it all—the uncertainty of adolescence, the thrill of success and respect, and the dark side that comes with getting it all and not having the wisdom or life experience to know when enough is enough. Beyond the haze of 1970s sexual freedom and rising equality comes both an intoxicating excitement—on-stage performances such as Joan Jett's "I Love Playing with Fire" and Cherie Currie's "Cherry Bomb," courageously sung by the actors, pop with a rattling and catchy sense of empowerment—and, ultimately, the poignancy and danger of innocence manipulated and stolen.

As things spiral downward, Sigismondi, too, slows the frames, placing the viewer inside Cherie's blitzed state of mind—a harbinger of destruction racing at breakneck speeds. Suddenly, all of the lights, all of the screaming fans, all of the magazine covers, and all of the concerts somehow don't seem quite as fun anymore. These girls—especially Cherie—have a lot of work to do before they can ever hope to enjoy and appreciate what it is they originally wanted to do: make good music. With band members Lita Ford and Sandy West not agreeing to participate in the picture's making, they are relegated to supporting parts, usually existing in the background of shots. This is Cherie's and Joan's story all the way, and they are always front and center to the action. Their makeshift friendship and fleeting sexual intimacy with one another at the height of their rise aren't shied away from, and neither is the drinking and drugs and partying that went along with being rock stars. Whereas Joan is viewed as having her head on fairly straight—for her, she wants to be taken seriously as an artist—Cherie is the tragic little girl lost, her insecure identity taken away from her and replaced with a marketable sex kitten. With a mother in Indonesia with her latest boyfriend and a father who is usually in an alcoholic stupor, who does she have to answer to and care about her? Add this to the list of her troubles.

Michael Shannon (2008's "Revolutionary Road") is a colorfully terrific Kim Fowley, alternately manipulative and abusive as he tries to rule The Runaways and finally drives them straight into the ground. With little to do, Stella Maeve (2005's "Transamerica") and Scout Taylor-Compton (2009's "Halloween II") carve out a few memorable moments to call their own as Sandy West and Lita Ford. By comparison, Alia Shawkat (2009's "Whip It") is but a glorified extra as Robin Robins and doesn't have more than a line or two of dialogue throughout. The rightful star attractions, though, are Dakota Fanning (2009's "Push") and Kristen Stewart (2009's "Adventureland") as Cherie Currie and Joan Jett. In her most adult role to date, Fanning is fearless, radiant and altogether devastating, the life and pizzazz in Cherie's eyes slowly drained away from her until she is but a shadowless shell of her former self. There is welcome redemption for her—and something of a bittersweet happy ending when she finally talks to Joan again years later over an admittedly impersonal radio talkback line—and the actress pulls off every nuance and character arc without even a hint of artifice. In a career that goes all the way back to 2001's "I Am Sam," 16-year-old Fanning has delivered what could be her finest performance to date. Not to be outdone, Stewart is raw, real and amazingly assured as Joan Jett, getting the look, the voice and the body language down pat. Consider this just one more reason why she desperately needs to finish the "Twilight" series of movies and concentrate on better, more personal projects.

Viewers looking for an encyclopedic treatment of The Runaways would do better to research them online. However, as a slightly more abstract and humane view of what it was like in the maelstrom of the group's highs and lows, the film is edgy, thoughtful and accurate. The pacing is fast and swirling, mimicking the group's life. The soundtrack is abuzz with classic songs of decades' past, as well as a compendium of The Runaways' greatest hits. Entertainment levels are consistently high, and so is the interest in where Joan's and Cherie's lives take them. Both are good people at heart and warrant a little happiness. That they got just that turns "The Runaways" into less a sob story than a cautionary tale with a rhythmic undercurrent. Things could have turned out quite differently for Joan Jett and Cherie Currie. The film acknowledges this, and is happy to turn the other cheek.