Mary (Mary McCormack Mary McCormack) has this secret identity, that is, a member of the Federal Witness Protection Unit, her job is to ensure the safety of witnesses and victims who have the courage to become witnesses, help them avoid criminals and send them to unfamiliar towns to start a new life. Ma Shaw (Fred Weller is acted the role of) is Mary's partner, although the two people with very different personalities always have all kinds of friction, but they have to admit that each other is their most trusted helper at work. Mary has a complicated and troublesome family, and her mother Jinx (Leslie Ann Warren Lesley Ann Warren) doesn't do her job all day, indulging in the paralysis caused by alcohol. Sister Brandi (Nicole Shields Nichole Hiltz) is locked up by her boyfriend Chuck (Tim Koch Tim Kelleher) and wants to help him transport a batch of methamphetamine out of the country.