How much do you really know about the people in your life? What you dont know could kill you in the terrifying new thriller THE STEPFATHER. When troubled teen Michael (Penn Badgley) returns home after a year at military school, he finds his mother, Susan (Sela Ward), in love and his soon-to-be stepfather, David (Dylan Walsh), has moved into their home. David says he wants them to become the perfect family. But as they get to know each other, Michael quickly becomes convinced that David himself is far from perfect.