When a psychotic woman sets her sights on a married businessman who refuses her advances, his wife is forced not to only fight for her marriage, but also for her life. 

Paige is an unstable woman on a mission to find a man to love. At her sister’s office Christmas party, she is introduced to businessman Jared Nelson, extremely attractive with a fun personality. Despite being told that he is happily married with two daughters, Paige feels an instant attraction and decides she will do whatever it takes to have him.

With no openings in jobs where she could be close to Jared, Paige creates an opening by murdering his secretary, then convincing her sister Olivia to get her an interview. Since she is related to Olivia, Jared hires Paige and they work together on a big project with an approaching deadline.

Things are good at home for Jared. His wife Karyn has a successful job of her own. Together, they are the parents of 15-year-old Rachael and 11-year-old Laura. The only issue for Karyn is that her husband has been living at work lately as he finishes work on a major drug study for his company. When a big wedding anniversary arrives, Karyn seeks advice from her sister Brenda on a dress to wear for the special night, only Jared says he has to work. He will make it up to her over the weekend.

Brenda suggests Karyn put on the beautiful dress and take Jared a piece of her wonderful lasagna she made for dinner. A surprise might be just what their marriage needs. Feeling like a teen in love, Karyn drops in on Jared at the office for a surprise. She ends up being surprised when she catches Paige cozying up to her boss. Karyn goes to leave in anger, but Jared convinces her nothing was going on between them.

After having a heart-to-heart with Brenda, Karyn realizes she may have overacted and apologizes to her husband at home. Things are back to being great between them again, something Paige can’t allow. She has managed to copy Jared’s keys and uses them to sneak into their house while they sleep. Karyn gets a creepy feeling someone watches her and snaps awake, only to find no one there.

From their kitchen, Paige sends Jared several suspicious texts from a burner phone, where she claims they were together sexually and she wants a relationship. Jared attempts to hide the messages from Karyn but she grows suspicious and looks at his phone. Jared swears someone is playing a joke or has the wrong number. The evidence is just too overwhelming. Following a fight in the kitchen, while Paige listens from hiding inside the laundry room, Karyn tells her husband to leave. He reluctantly complies. To speed things along, Paige removes her underwear and stuffs them into a pocket of jared’s clothing in the dirty laundry. When Karyn finds them, she realizes she was right about the affair. 

Wanting Jared and the girls for herself, Paige pretends to be Karyn so she can sign Laura out of school. Then she assaults Karyn and holds her hostage. With the help of his dad, Jared locates the cottage where Paige has gone and battles against her to save his family.