Life has not been kind to Claireece “Precious” Jones (Gabourey Sidibe), an obese, illiterate, black 16-year-old growing up in Harlem. It does not take long for Lee Daniels’ coruscating film to establish the harrowing details; our heroine has just been raped and impregnated by her father for a second time; her mother (Mo’Nique), a monstrous wreck of a woman, doles out additional physical, mental and sexual torments on a daily basis.

Precious frequently pines for her first child, known only as ‘Mongo’ (short for “Mongoloid”), but the girl has Down syndrome and is being cared for by her grandmother. Our heroine desperately needs an intervention and she gets one when her junior high school principal arranges to have her attend an alternative school.

But will support from a dedicated teacher and a social worker (Mariah Carey and Paula Patton, both excellent) be enough the break the awful cycle?

Director Lee Daniels, working from an Oprah-endorsed novel by Sapphire, fashions addictive melodrama from savage social circumstances. What might have been just another Salvation in the Hood routine with is delivered with a unique authorial stamp pitched somewhere between social realism and mythmaking. Even potentially over familiar devices such as Precious’ escapist flights of fancy are given novel expression.

Much of the film’s brave realism and potency relies on Gabourey Sibide and Mo’Nique, both of whom turn in outrageously good performances. For all the horrors of Precious’ world, there’s an energy around this project and an innate belief that somewhere out there, people will give a damn. Our heroine may not get the red carpet fairy-tale ending she deserves and frequently fantasises about, but she may just get a shot.