USA Network's newest original series stars Mary McCormack (Private Parts and The West Wing) as Mary Shannon. Her friends and family think she's just a glorified courier, but she's actually a U.S. Marshal, working for the highly secretive Witness Protection Program. Her job is to help relocate federal witnesses. Whether they're career criminals, or just people who had the misfortune to witness a crime, they all share one thing in common – somebody wants them dead. Co-starring Frederick Weller and Lesley Ann Warren.