Meryl Streep may be the greatest actor working today. Her chameleonic portrayals never fail to astonish; she seems actually to be the characters she brings to the screen. In "One True Thing," she gives life to a deceptively straightforward, profoundly complex woman doing her best to play the hand life has dealt to her. Surviving with cancer is no easy task, and not just surviving but actually continuing to live one's life is even harder--and this is precisely what Kate Gulden (Streep) means to do. Renee Zellweger ("Jerry Maguire") not only holds her own in this exalted company but shines as Streep's daughter, who learns to see in a new light her parents' lives as well as her own. Streep is a powerhouse and deservedly received an Oscar nomination for her work here; her "I'm only going to say this once" dialogue with Zellweger will leave you devastated. Zellweger, though, is the real revelation--her face conveys every emotion, every conflict as she begins to learn the many truths about her parents' strengths and weaknesses. Director Carl Franklin ("Devil in a Blue Dress") handles the extremely difficult story material with sureness and delicacy.