What Lies Beneath (2000)

What Lies Beneath is a 2000 American supernatural horror film directed by Robert Zemeckis and starring Harrison Ford and Michelle Pfeiffer as a couple who experience a strange haunting of their home. It was the first film by Zemeckis' production company ImageMovers. The film opened in 2,813 theaters in North America, and grossed $291 million at the worldwide box office, becoming the tenth-highest-grossing film of the year. It received mixed reviews, but was nominated for three Saturn Awards.

After her daughter Caitlin leaves for college, Vermont housewife Claire Spencer begins noticing the volatile relationship between new neighbors, Mary and Warren Feur. Claire's husband Norman, an accomplished scientist and professor, dismisses her preoccupation.

After failing to see Mary for several days, Claire suspects that Warren may have killed her. Claire sees the image of a woman floating in the lake, and discovers an odd key inside a heater vent in her home. Claire and her mystic friend Jody unsuccessfully hold a séance to contact Mary, after which Claire finds the bathtub filled with hot water and, "You know," written on the mirror. Claire then finds her computer inexplicably typing "MEF" repeatedly. Claire becomes convinced Mary is haunting her, but Norman is unconvinced. Several days later, Mary returns home alive and well, saying that she was with her mother in Rhode Island after a fight with Warren.

In a broken picture frame, Claire finds a newspaper clipping of a missing woman named Madison Elizabeth Frank, who bears a striking resemblance to her, and whose initials match "MEF." Claire tracks down Madison's mother and steals a lock of Madison's hair from a photo in the home in which Madison is wearing an unusual necklace. Later that night, Claire reads about conjuring the dead, and becomes possessed. When Norman arrives home from work, Claire's personality has noticeably changed, and she aggressively seduces him. However, the encounter is interrupted when Claire recalls a repressed memory of discovering Norman's affair with Madison, his student. Norman admits to the affair, and Claire spends the night with Jody, who reveals to her that she had witnessed Norman arguing with a blonde woman at a cafe in the nearby town of Adamant about a year earlier.

Claire returns home and finds Norman in the tub after an apparent suicide attempt, but he recovers. Claire asks Norman if he killed Madison, which he denies. He then witnesses Claire being drawn to the lake, where an unseen force pulls her under by the lock of Madison's hair in her hand. It pulls her down to the bottom, where she finds a box with the same symbol as Madison's necklace. Norman saves Claire from the lake, and the two burn the hair. After visiting Adamant and spotting ornate lockboxes at a shop, Claire recovers from the lake an identical box, which she unlocks with the matching key; inside, she finds Madison's necklace. Norman changes his story, claiming that Madison killed herself in their home, and that he pushed her car into the lake with her inside. Norman agrees to confess to authorities, calling 911 to explain the situation. Claire redials the phone to discover that he actually dialed 411, faking the conversation. Norman attacks her, paralyzing her with halothane, and finally admits to murdering Madison to prevent her from exposing their affair to the dean of the university and that he faked the suicidal attempt.

Norman places Claire in the bathtub, filling it with water and staging a suicide for her. He spots Madison's necklace around Claire's neck; as he moves her, her face contorts to that of Madison's corpse; Norman jerks away, and smashes his head on the bathroom sink, rendering him unconscious. Recovering from the paralysis, Claire manages to shut the tap off in time to save herself from drowning. She finds that Norman has left the bathroom and discovers him seemingly unconscious downstairs. She flees in the couple's truck, which has their boat hitched to the back. As she is crossing the bridge over Lake Champlain, Norman attacks Claire, who frantically dials 911 on her cell phone and causes the truck to careen down the embankment into the lake and dislodge Madison's car. Disturbed by the debris, Madison's corpse floats toward the couple and avenges her own death, drowning Norman and allowing Claire to swim to the surface. Later in the winter, Claire places a red rose on Madison's grave.