Description
Clint Goodman is a successful contractor who built his comfortable house and his construction company in his hometown through hard work. He loves his wife Joanna, but she is resentful of him most of the time; the couple has been trying unsuccessfully to have a baby. Clint's best friend is Sheriff Sam Eberly. Every now and then, they spend the night fishing on the lake.
Unknown to Clint, Joanna has been having an affair with local doctor Cortland van Owen. He plans to kill Clint and have Joanna sell his company and house. With the money, they will move to Beverly Hills to buy a clinic. Cortland gives poison to Joanna, taken from a poisonous tropical fish. Though hesitant at first, Joanna goes along with the idea. While having dinner with Clint, she begins to have a change of heart and starts pouring the poison away at the kitchen sink, but stops herself. She spikes his wine with the poison, but is startled by Clint and drops the vial with a small amount of the liquid left In It. After drinking the poisoned wine, Clint has a heart attack and apparently dies. When the coroner asks if an autopsy should be done, Cortland refuses. While Clint's body is at the morgue, he shows signs of life. Just before he is to be embalmed, Joanna instructs that he be given a quick and cheap funeral instead, skipping the embalming process. Clint is placed in a cheap water-damaged casket, varnished to look like new. After his funeral, Joanna and Cortland celebrate.
During a stormy night, Clint, who has survived the lower dosage, wakes up, finding himself buried alive. After breaking through the coffin lid and escaping his grave, he returns to his house and learns the truth about his wife and the doctor. He hides in the basement to recuperate. The next morning, Joanna meets with a lawyer to discuss selling Clint's business for $1,500,000. Clint plans to kill Joanna, but when Cortland comes by to visit her, Clint overhears that Joanna was pregnant and that she and Cortland had had his child aborted behind his back. Convinced that merely shooting her would be too easy, Clint plots a dark revenge against Joanna and Cortland. That night, while Joanna is passed out from sleeping pills, Clint cleans himself up in their bedroom bathroom and tends to his injuries.
The next morning, after Joanna has sold Clint's business and collected the money, Sam discovers that Clint's grave has been disturbed and the body is missing. Examining the coffin, he realizes that the hole in the coffin lid was made from the inside, and so believes that Clint could still be alive. Joanna goes into the bathroom and finds the floor and tub covered with mud. Suspecting that someone has been in her house, she frantically calls Cortland (only getting his answering machine) and is startled by Clint's dog, Duke, whom she chased away earlier. Just as she's about to shoot the dog, Clint, disguised in a welding mask and body armor, appears from behind the open basement door. Surprised, she falls in the basement, knocking herself unconscious, while Clint locks her inside and boards up the basement windows.
Meanwhile, at his apartment, Cortland loads a syringe with more fish poison and leaves after listening to a recorded message from his landlord demanding payment of unpaid rent - but just before Joanna's message is played. Arriving at Clint's house, he is unable to find Joanna, but finds the money in a suitcase on the bed, which he takes. Searching for Joanna, Cortland enters the basement, the door of which is now open. Believing Cortland to be the masked figure, she knocks him unconscious with a blow to the head, causing him to drop the syringe which rolls out of view. She then takes the money and tries to escape, but Clint locks them both inside. As Cortland regains consciousness, Joanna realizes her mistake, at which he argues about burning the money to prove his love. Cortland tries to open the door by shooting the lock with the shotgun, only to discover that Clint has replaced all the shells with blanks, In the meantime, back in the house, Clint knocks out some walls and moves furniture, with Duke guarding the basement windows and preventing the pair from escaping.
While they wait for the figure to hopefully release them, Cortland suspects that Sam may be behind everything and that he wants the money. Joanna then finds the fish poison syringe and realizes that Cortland was going to kill her. Cortland shows his true colors, revealing that there never was a clinic; his real intention was to take the money for himself so that he can move to the tropics and live an easy life. They fight, and just as Cortland is about to use the syringe on Joanna, the door opens. Exiting the basement, the pair finds out that most of the house is now blocked off by wooden panels. While trying to find a way out, they are led through a maze and separated by sliding panels. At the end of a passage leading to an unblocked window, Cortland sees a shadowy figure and, still thinking it's Sam, tries to bribe him, secretly planning to inject him with the poison. Clint reveals himself, saying "Keep it"; a stunned Cortland tries to flee, but trips on the briefcase of money and falls, accidentally injecting himself with the poison and killing himself. Shortly afterwards, Joanna is trapped between Clint and a small hatch. As her only option, she crawls through the hatchway along a low passage to where it suddenly dead-ends, allowing Clint to shut her inside. Clint reveals himself to her and mentions their aborted child, asking if it was a boy or a girl. He dumps the dead Cortland and the money inside with her in what is now a large wooden coffin. and nails it shut. He then loads it onto his truck and sets fire to the house before leaving with Duke.
Sam, who now believes that Joanna and Cortland either murdered or tried to murder Clint, rushes to the house to find it ablaze. After the fire is extinguished, no bodies are found inside the house. Returning to the cemetery, Sam sees a man standing at Clint's re-filled-in grave, with his back to Sam. Realizing it is Clint and presumably realizing his revenge scheme as well, Sam tells him to never come back, obliquely promising to keep his secret. Clint and Duke drive away, and the final shot reveals that the still-alive Joanna and the dead Cortland now occupy Clint's grave, with the money.
