Mo'Nique as Precious's mother, Mary.
She's also at the mercy of a mother (Mo'Nique, dead-eyed and terrifying) who beats and humiliates her; Mom's resentful rage intensifies when Precious enrolls in a new school under the gaze of a devoted teacher (Paula Patton). (Other supporting players include Lenny Kravitz
as the world's hottest nurse and a perfectly dowdy Mariah Carey
as a social worker.)