Casey Cooper, Amanda Righetti works at a café. She has to train a new employee, called Morgan Pierce, Will Estes. He's a weird boy, and quits without telling anyone the reason. Suddenly, he starts calling Casey up, and insisting. He mentions odd stuff to Casey, the boss and owner of the coffee-shop Annette Bramble, Catherine Hicks, and his own replacement, new trainee Lauren, Krysta Rodriguez. Morgan keeps on calling Casey, to her mobile phone, to her home number. He follows and videotapes her everywhere. Morgan follows Casey to her other job, a bartender at a bar, and harasses her there as well. Her workmate behind the counter offers to accompany Casey home, but she is not afraid. However, Morgan follows her at night, but a man tells him to get in a car.
Once, Morgan enters the shop and accuses her of murdering hundreds of people, saying that she’s telling him and that the news is in the newspaper. Casey pushes him away to make him go. Morgan complains to the police that she is harassing him and that she has attacked him. Officer Hughes, Michael Patrick McGill and Officer Williams tell Casey that they can’t do anything for her unless Morgan clearly states that he wants to kill her. Although Morgan retracts his accusation, he’s free in 24 hours. The officers recommend Casey to tell her predicament to Detective Dominic Leary, Eric Szmanda, who is a specialist in the field.
Casey lives with her sister Toni, Christie Burson, as they have a home bought together with a shared mortgage. Casey is also a freelance writer.
Detective Dominic Leary tries to check Morgan’s background. He’s got some previous convictions, but he can’t access them, and he is told by his bosses to let Morgan be. Little by little, Morgan stalks Casey more and more.
Morgan’s father Richard Steele, Harry Hamlin is fooled by his son into believing that Morgan is taking his medication. The pressure continues, and Casey becomes a nervous wreck. Annette offers a cabin in the woods so that Toni and Casey can spend some days alone there. Also, Leary recommends Casey to protect herself by all means. Toni buys a gun. When they arrive at the cabin, they realize there is no mobile phone coverage, but they can access the neighbors’ Wi‑Fi connection. The girls are having fun when, suddenly, Morgan appears.
Morgan Pierce tries to strangle Toni, but Casey scares him away with Toni’s gun. This time, there is a reason to check Morgan’s previous sentences and to obtain a search warrant. Morgan is on the run. It turns out that Richard Steele is the estate vice-president, but Morgan is using his mother’s single surname to shield his father from bad publicity. Richard wants to talk with Casey, so he goes with Leary. Richard accuses her of trying to seduce Morgan. Leary and Casey press for action, and nobody can easily capture Morgan. Casey writes a piece in the newspaper about her experiences.
Time passes. Annette Bramble leaves the shop and Casey is left alone in the café. There is a police officer watching outside, but he is taking a break on the toilet for 20 minutes. Morgan returns, more wrecked than before. He threatens Casey and finally states that he wants to kill her. Leary and other police appear from all over, eventually trapping him. Leary tells Casey that his bosses want to create a department with Casey’s help to support other victims of stalkers.
