When Lisa's father is assassinated in a hit-and-run, we learn that he has a secret daughter from his previous marriage. Marie is a convicted murderer who has been granted an early release from jail and is driven by a single objective–vengeance. Marie has connived her way into living and working near to Lisa, lurking and plotting her revenge for the life she feels she has been robbed out of–a life she believes their father unfairly handed Lisa. Marie has devised a lethal trap for Lisa in order to get what she is due, leaving Lisa, her mother, and their friends fighting for their lives against the vicious sister Lisa never knew existed.