Mystic River is a crime drama film that features Laura Linney in a supporting role as Annabeth Markum, the wife of Sean Penn's character. The movie revolves around the lives of three childhood friends who are reunited after a tragic event. Linney's character adds emotional depth to the story as she grapples with the aftermath of the tragedy and the secrets that unfold. Mystic River is a gripping and intense film that explores themes of friendship, loyalty, and the consequences of past actions.