Warning a potential client about the perils of divorce, a chain-smoking attorney named Gavin D’Amato tells the story of Oliver and Barbara Rose, who met at a Nantucket estate auction, both bidding on the same, mistakenly undervalued 18th-century Chinese homunculus statuette. When Barbara outbids Oliver, the two become attracted to each other, make love, and decide to marry. Three years later, the Roses have a family of boisterous twins, Josh and Carolyn, who distract Oliver from his efforts to complete a Harvard University law degree. One Christmas Eve, Oliver is busy with his studies, but Barbara insists they go for a walk and surprises her husband with an antique Morgan automobile. In the years to come, Oliver becomes an associate lawyer at a firm with Gavin, and angles for a more prestigious role. Sometime later, Barbara discovers that the owner of her “dream home” has died, and the Roses move into the mansion. Over the next six years, Oliver becomes a senior partner while Barbara refurbishes the house. Once the remodeling is complete, Barbara announces her plan to start a small business, selling pâté to fellow housewives. Anticipating a lucrative enterprise, Barbara buys an enormous sport utility (SUV) truck for $25,000. As her business flourishes and the Rose twins prepare to attend Harvard, Oliver persuades his wife to hire a live-in housekeeper named Susan. In time, Oliver’s ambition becomes a source of great annoyance to Barbara, who is trying to promote her new catering career. When Oliver fails to read her catering business contract, an argument ensues, and Barbara uses her strength as a gymnast to squeeze Oliver’s waist between her thighs. At a lunch meeting the following day, Oliver convulses in pain and believes he is dying from a heart attack, but soon learns he has a harmless hernia and attributes it to Barbara’s leg grip the previous evening. When Barbara fails to arrive at the hospital, Oliver returns home with a note he scrawled when he thought he was near death, declaring to Barbara: “All I am and all I have I owe to you.” However, Barbara is unmoved. She later confesses that she felt happy at the prospect of Oliver’s death and asks for a divorce. Sometime later, the couple meets Barbara’s divorce lawyer, Harry Thurmont, who states that Barbara wants nothing from Oliver but the house and its contents. When Oliver insists that his earnings paid for the home, the attorney quotes Oliver’s “deathbed” note. Enraged, Oliver declares war on his wife and vows she will never get the house. He seeks legal support from Gavin, who shows Oliver a little-known precedent stating that a divorcing couple can still live under one roof. Gavin suggests Oliver move back into the house to demonstrate his commitment to the property. On Christmas Eve, the Rose family awkwardly gathers around their decorated tree. The lights dim, and Barbara declares that there is a short circuit, but Oliver insists the blackout is due to a misplaced ornament. Later that evening, the tree catches fire and Barbara gloats over Oliver’s error. On another night, Barbara refuses to share her sleep medications with Oliver, and he accidentally kills her beloved cat on his way to the pharmacy. Taking revenge, Barbara locks Oliver in his sauna. Although she lets him out, hoping he will finally relent and leave the house, Oliver’s conviction only grows stronger and he later saws the heels off Barbara’s extensive shoe collection. In yet another attempt to rid herself of Oliver, Barbara attempts to seduce Gavin, hoping he will reason with Oliver. Soon, the twins leave for college and Susan ends her employment at the house. When Gavin warns his client to end the battle, Oliver fires the attorney and proceeds to disrupt Barbara’s business dinner party. Enraged, Barbara drives her SUV over Oliver’s restored Morgan as her guests watch in horror. On another evening, during an electrical blackout, Barbara invites Oliver to a candlelit supper and both are suspicious of being poisoned. When Barbara begs Oliver to leave yet again, he confesses that he still loves her and wants to restore their relationship. In retaliation, Barbara declares that her liver pâté is made from Oliver’s dog, Bennie. While the dog sits in the yard unharmed, Oliver chases Barbara through the house and nails the front door shut, so neither can leave. Barbara hides in the attic, but Oliver finds his wife and attempts to rape her. Playing along, Barbara bites her husband’s penis. Just then, Susan sneaks back into the house with concern for the couple and Oliver forces her to go away. He drunkenly sings to Barbara and lures her out of hiding with the announcement that he has a “gift” for her – the 18th-century Chinese homunculus statuette that Barbara won in the estate auction the day they met. As she reaches for it from the top of the stairs, Oliver pulls a string he attached to the ornament and snatches it away. Referring to the antique that provoked their bidding war years earlier, Oliver declares that he will give Barbara everything in the house if she says: “It’s mine.” Twisting his words, Barbara replies, “It’s mine,” inferring that the homunculus belongs to her. In response, Oliver smashes the artifact with an iron poker and Barbara bends over in pain, covering her eye. Oliver runs up the stairs to help, but she retaliates, hitting him with the rod. Losing balance, Barbara falls through the banister and clings for life to the foyer’s chandelier. Oliver offers to save her in return for the house. When he tries to catch the chandelier with the iron poker, he, too, is trapped on the light fixture. Outside, Susan waits for Gavin to respond to her urgent call for help. When he arrives, the couple begs him to get a ladder, but it is too late. The chandelier smashes to the ground. In his last moments of life, Oliver places his hand on Barbara’s shoulder, but she weakly tosses it aside, and Susan and Gavin find the couple dead. Back in the present, Gavin warns his new client that there is no such thing as a civil divorce and suggests that he try to restore love in his faded relationship. The attorney then finishes his last cigarette and goes home to his new wife.