In Sherrybaby, the emotionally arresting new independent feature written and directed by Laurie Collyer, Maggie Gyllenhaal plays a young New Jersey woman who’s a recently released convict, a recovering junkie, and — more than that — a totally annoying dim-bulb narcissist. Yet from the opening of the movie, she has you hanging on her every word and gesture. Blond and beaming, she speaks in a slack, dazed little-girl voice — the sound of a burnout looking for the next sensation — that makes her sullen sexuality seem an eruption from within. Sherry believes in her willowy body and not much else. She’s a cherry-bomb hellion who never grew up; she wants and wants, and gives too little in return. Yet Maggie Gyllenhaal is such a miracle of an actress that she makes you respond to the innocence of Sherry’s desperate, selfish destruction. I was gripped by the way that she holds a cigarette, her two fingers stretched out in a girl’s rigid notion of ”maturity,” and by the way her head dips slightly, with sulky sensuality, like something out of an old Cyndi Lauper video. You may not like the character — you’d be deluded if you did — yet your heart opens up and bleeds for her.

Out of prison (her drug habit had turned her into a thief), Sherry moves into a Christian halfway house, where she’s tough enough to swat away a combative fellow resident yet not smart enough to keep from dropping her miniskirt for the guy who runs the recovery program. As soon as we see these two in the basement, going at it, we realize what Sherry is up against: not just a history of drugs or a punitive probation system but her own sleazy, myopic, live-for-the-moment nature. Sherrybaby builds our sympathies around a fantastic ambivalence. Sherry has a daughter, Alexis (Ryan Simpkins), who has been raised by Sherry’s brother and his wife (Brad William Henke and Bridget Barkan), and when she goes over to their house and gives the girl a tearful hug, telling her that ”Mommy” is back, you can’t help but want these two to be together. Yet you also know it would be a disaster. Sherry can barely take care of herself, let alone a child. She hasn’t earned this girl. The film is all about how she struggles to.

Collyer, who has worked in documentaries, brings us so close to Sherry that we’re sympathetic and aghast, often at the same moment. Gyllenhaal has a great scene in which Sherry embarrasses her family by singing the Bangles’ ”Eternal Flame” at a dinner party, yet what makes it powerful is that we can see that she’s been doing this ever since she was a girl, when it was probably charming. Gyllenhaal never lets you forget the damaged child, the baby, under Sherry’s jaded facade. The movie ultimately shows you how she got that way, but it never lets her off the hook. Danny Trejo, as the hulking dude who befriends Sherry at a recovery meeting, has a marvelous been-around-the-block tenderness, yet even he can’t ”save” her. No one but Sherry can, and watching her try, fail, and try again makes for one of the most authentic, and moving, journeys the movies have offered this year.