Emily returns to Southampton and rents the seaside home she shared with her father, David Clarke (James Tupper), 17 years ago. With the help of her only friend, Ashley, she sets her sites on her first target, and puts her carefully organized plan in motion. Her focus unexpectedly wavers when she comes across Jack, a friendly face from the past, makes a new romantic connection with the son of her sworn enemy, and is pushed into an uneasy alliance with the only person who knows her secret.