Don Champagne, portrayed by Patrick Wilson, is married to the controlling and ambitious Mona Champagne, played by Katherine Heigl. Together they are parents to two children, Andrew and Allison. Don is the owner of a furniture business while Mona exerts a significant influence over both family and career decisions, often implying that their lifestyle is funded by her family's wealth.
For the business, Don employs salespeople Les, portrayed by Jim Belushi, and a new sexy hire named Dusty, played by Jordana Brewster. Dusty enters their lives unexpectedly, applying in-store without Mona’s knowledge, and her alluring presence quickly disrupts the mundane routine of the Champagne household.
Mona is noted for her meticulous planning and has a "goal book" that outlines aspirations for the business—including a retreat in Florida and the establishment of a second store. However, her strictness extends even to intimacy, scheduling their intimate moments a mere six times a year. As tension rises, Mona discovers Dusty’s true allure during a surprise visit to Don's workplace.
Faced with mounting sexual frustration and dominance from Mona, Don finds himself succumbing to Dusty's advances shortly after their initial encounter. They embark on a series of passionate escapades, leading to a shocking revelation when Dusty claims to be pregnant and appears in a bikini at a barbecue hosted by Mona. It becomes clear that Dusty's true intentions are far from innocent; she is part of a larger scheme with accomplices Murphy and Freeman.
After a strategic conversation with Les, Don decides to pay off Dusty but is caught off-guard when she demands even more. Not wanting to risk a confrontation with Mona, he confesses his infidelity, expressing a desire to remain committed to their family goals, while Mona concocts a plan to eliminate Dusty rather than face the consequences of Don’s actions.
The plots intensify as Mona instructs Don to drug Dusty during their meeting the following night. As the plan unfolds, things take a dark turn when Mona ends Dusty's life with a hammer after a near escape. Don struggles with his role in this chilling affair while his wife dismembers the evidence, claiming that Dusty's pregnancy was a ruse all along.
Feeling the pressure from Dusty’s accomplices, the couple digs up her body to meet with Murphy. But more bloodshed follows when Mona is forced to eliminate threats from Freeman and his girlfriend. In a chaotic turn, the police arrive to a scene where the truth begins to unravel, implicating Don and Mona.
As paranoia sets in time and time again, Don contemplates how far Mona's cold-blooded nature stems from her upbringing, only to receive a chilling warning to keep such thoughts to himself. With their lives spiraling into a series of tragic events—culminating in Don staging a fatal accident against Mona—he attempts to escape their grim reality with his children.
In an unsettling finale, viewers witness their departure from the scene, leaving the impression that danger continues to stalk them, as Murphy's relentless pursuit suggests that the story is far from over. The screen fades to black, with audio hints of violence, drawing the story to an eerie conclusion.
