A father hires a live-in nurse to help care for his sick daughter, however, as she suffers a series of setbacks, he starts to wonder if the nurse might actually be the one keeping her sick.

After losing her husband and daughter in a car accident involving Amy Martin, Catherine falls into a deep depression and blames Amy for the tragedy. She begins stalking Amy's family, including Liam and Corinne, and applies for a job as Corinne's live-in nurse under the name Victoria Jones. Catherine uses a fake identity as a former patient named Eleanor to secure the job and sets her sights on replacing her lost family with Liam and Corinne.

Catherine wins them over with her charming personality, even wearing Amy's dresses. She poisons Corinne's tea in an attempt to get closer to Liam, but Beverly, Liam's coworker, drinks the poisoned tea and confronts Catherine. Catherine drugs Beverly and tries to drive a wedge between Liam and his mother-in-law by planting a pamphlet about child custody. Liam becomes suspicious of Victoria when he realizes she is not from the agency that sent the other applicants.