Connor, a man whose dull life is transformed into a thrilling fantasy world thanks to the seductive Marilyn.
After spending time in prison following an assault charge, Connor Bates now works in a library and spends his free time running, swimming, and trying to piece his world back together. When he meets Marilyn Chambers, the wife of a wealthy businessman, they collide into an intense physical and emotional relationship that quickly escalates into idle talk about her husband's murder.
Connor Bates (Ray Nicholson) is a young man who lives in the basement of his mother's house in a small Rhode Island coastal town. He works in the local library, which, by his own admission, is the only place that would have him due to his criminal record. Connor has been in prison for three years on an assault charge. Besides navigating the labyrinthine library aisles and enduring his antagonistic probation officer's Jock (Hank Azaria) hostile tirades about tardiness, he's a dedicated jogger pounding the pavement along the coast as an outlet for his emotions.
One morning, while jogging, Connor meets Marilyn (Diane Krueger), an attractive, blonde older woman... and the femme fatale of this story. Connor can't help but notice the woman in the bright red swimsuit. Introductions are made, and a current of flirtation crackles between them. The connection between Marilyn and Connor is immediate.
Marilyn shows up a day or two later at the library where Connor works sporting dark sunglasses to hide a bruise on her face. She asks Connor if she could check out some books about crime and murder. He suggests the novel 'The Postman Always Rings Twice' about a drifter who is conned into committing a murder by a wealthy older woman. Marilyn leaves her home phone number on a dollar bill that she leaves.
Against his better judgment, Connor makes the phone call one day and he and Marilyn talk. During another get together, Marilyn tells Connor that she is married to a wealthy businessman named Richard (Victor Slezak) who is abusive towards her and her teenage stepdaughter named Astrid (Chase Sui Wonders).
In the many subsequent rendezvouses, Marilyn gradually confides in Connor: she claims that her husband beats her and is also abusive towards his own daughter. Their secret meetings fan the flames of desire. With each encounter, the physical tension between them intensifies, threatening to erupt into something more. Meanwhile, a colleague at the library named Kim (Gia Crovatin) also seems to like Connor. Kim tells Connor that Astrid is dating the known local playboy, Jared (KeiLyn Durrel Jones).
With time, the sexual affair between Marilyn and Connor gets stronger, and Connor starts to feel protective of Marilyn. And so grows the desire within Connor: the desire to rescue Marilyn and Astrid from the grip of their tormentor. In the face of the possibility of the end of his relationship with Marilyn, Connor offers to take matters into his own hands. He tells Marilyn that he will kill her husband. So, they start to hatch a plan on that: Marilyn would take Astrid and go away for a trip on her husband's yacht. Then, Connor would go to their house, find Richard, and then would kill him. Connor does the first two tasks. The final task of the killing does not go as smoothly as he has hoped for...
Connor struggles to kill Richard, and in the scuffle, the husband gets the upper hand as he gets the gun. Just when he is about to pull the trigger and end Connor's life, another intruder hits him on the head and instantly kills him. This intruder is revealed to be Jared, Astrid's boyfriend. Jared says that he came here on Astrid's orders to burglarize the place and it is a coincidence that Connor and he chose the same night for their respective crimes. However, Connor does not quite believe that and kills him.
After the killings, Connor gets a call from Marilyn a couple of days later. He confronts her as he thinks that Marilyn and Astrid have sent their respective boyfriends for the same murder-for-hire job or there was something that Marilyn did not tell him. Marilyn denies that. A few more days pass by, and Connor finally gets the predetermined message that indicates Marilyn wants to meet him. However, the moment Connor steps out, he gets surrounded by police and his probation officer Jock who plan to arrest him for the two murders. A chase ensues and Connor gets cornered in the spot where Marilyn was supposed to come. Realizing (way too late) that Marilyn set him up as the fall guy for her husband's murder, Connor has a mental breakdown. Despite Jock's best efforts, a policeman fatally shoots Connor, misreading Connor's movement of reaching into his pocket for his phone. Connor dies with the vision of Marilyn in her red swimsuit, the one she wore when Connor saw her first time.
Another day or two later, on a private yacht, Marilyn and Astrid have a conversation about not returning a library book that Marilyn checked out. It is 'The Postman Always Rings Twice'... and the inspiration that Marilyn got the idea to set up Connor to kill her husband. Marilyn and Astrid end up kissing each other... revealing that they are lovers. It is speculated that years earlier, Marilyn married Astrid's father not only for them to be romantically together, but for the reason to conspire to murder him so that both of them could inherit all of Richard's money. Marilyn had been spying on Connor for some time and used his ex-convict status and his mental fragility to get him to kill her husband, while Astrid (under Marilyn's approval) also did the same to Jared. Now that they have completely gotten away with everything, Marilyn tells Astrid that with their plan complete, nothing will ever again come between them.
