Ian Mitchell is a lawyer and father who one day receives a box containing a gun and a picture of a stranger, along with instructions to kill the pictured person. He is subsequently attacked by another stranger, and discovers that he has been chosen by a mysterious organization known as The Watchers to participate in a lethal game.

Follows the story of the challenging relationship between Billie and her younger schizophrenic sister, Elizabeth Baby. After their mother dies, Billie takes responsibility by moving Baby in with her family, including her husband, their teenage son and young daughter. At first, Baby and the family work to adjust to their new living arrangement. However, after a disturbing incident involving her son and Baby, it becomes clear to Billie that she and her family are not equipped to handle Baby's illness, ultimately forcing her to make the difficult decision to do what's best for her sister and her family.