Fatal Instinct

While on a stakeout at an amusement park in Los Angeles, California, police detective Ned Ravine (Armand Assante) is approached by a flirtatious, sultry blonde woman (Sean Young). However, he must leave her to pursue culprit Milo Crumley (Blake Clark), known as the "pantyhose bandit." After arresting Milo, Ned, who is also a defense attorney, offers to represent him in court.

At his law office, Ned relies on his devoted secretary, Laura (Sherilyn Fenn), who is always efficient except when tortured by flashbacks of her abusive husband. After successfully defending Milo in court, Ned receives a surprise visit from Lola Cain, the blonde woman from the amusement park. The beautiful seductress asks Ned to meet her the following evening to look over some papers that she cannot understand.

While workaholic Ned is on police duty at night, his wife, Lana Ravine (Kate Nelligan), has been having an affair with auto mechanic Frank Kelbo (Christopher McDonald). Lana asks Frank's advice about her husband's accident insurance policy, and learns that it contains a triple indemnity rider worth $9 million, if Ned is shot with a pistol, falls from a northbound train, and drowns in a freshwater stream. Undaunted by the complications, Lana plots to murder Ned that weekend while he travels to a legal symposium in Santa Barbara, California, and agrees to share the insurance payout with her lover. She instructs Frank to tamper with Ned's car, so he will be forced to take the train.

At his office, Ned receives instructions to meet Lola at Le Hot Club and from there, the two proceed to her mansion. After looking over her "papers," a laundry receipt and a lottery ticket, Ned succumbs to Lola's sexual advances and engages in various erotic scenarios with her throughout the house. In the morning, Ned reminds Lola he is married and cannot continue their affair. The rejection shocks Lola, and she gives Ned a deranged look.

Meanwhile, criminal Max Shady (James Remar) is released from prison and is determined to take revenge on Ned for losing his case seven years ago. Laura shows Ned the multiple death threats Shady has faxed to the office, but the attorney believes the criminal just needs to vent his anger and is not concerned.

At home, Ned wants to make amends with his estranged wife and buys her a pet skunk, but she is unimpressed and remains focused on killing him. When Ned treats Laura to shopping and dinner for her birthday, she looks at her handsome boss with affection, hoping he will take an interest in her. At the restaurant, an obsessive Lola interrupts them and threatens Ned with an ice pick, giving Laura another reason to worry about her boss's safety. Unable to use his car after the engine goes missing, Ned initially considers flying to Santa Barbara. He is fearful about taking the train since several members of his family have been killed in train wrecks, but Lana persuades him and advises that he stand in the vestibule between cars to calm his nerves.

Lana and Frank secretly get on the train with Ned, who is also being followed on board by Max Shady. As the train leaves the station, Ned is anxious and sweating. After he gets up from his seat and walks toward the vestibule, Lana follows. She enters the area and shoots a man in the back, who is standing by the exit door and wearing a suit similar to Ned's. She believes she has shot her husband, but the man who falls out of the train, riddled with bullets, is Max Shady. Ned appears from the adjacent bathroom and is grateful to his wife for risking her life to protect him. However, as a police officer, he must arrest her for Shady's murder, but agrees to serve as her defense attorney.

At the murder trial, Ned succeeds in convincing the jury that his wife should be acquitted. As soon as she is free, Lana kills her accomplice Frank over concerns he might betray her. Lola witnesses the deed and blackmails Lana. Ned walks in the house as Lola is talking to his wife, and denies knowing the blonde woman.

Later, an angry Ned goes to Lola's mansion and warns her to stay out of his life. During their altercation, Lola reveals that Lana is her identical twin sister, who stole her boyfriend Dwayne, the love of her life. When a confused Ned remarks that the two women look completely different, Lola explains that Lana destroyed her original face with a shovel and she had to endure fifty-three plastic surgery operations. Ned is amazed at the beautiful result, but Lola disagrees, calling herself "ugly." She says Dwayne abandoned her for Lana after he saw her transformation. Lola's attempt to destroy her sister's marriage to Ned was part of her revenge. She also tells Ned that Lana murdered the mechanic. When Ned informs Lola that the mechanic's name was Frank Kelbo, she is devastated, realizing that Frank was the son of Dwayne, whose last name was Kelbo.

Returning home, Ned finds hot water running in the bathtub, but his wife is absent. Laura, who has been conducting her own investigation, arrives to alert Ned that his wife and Frank were plotting to murder him so they could collect on his insurance policy. She also confides about her difficult past and fleeing from her obsessive-compulsive, abusive husband. As Ned and Laura talk in the kitchen, Lana saws a break in the upstairs handrail, but Lola surprises her sister and drowns her in the bathtub. When Ned goes to investigate the faucet noise, he discovers his wife's dead body and is assaulted by Lola.

Meanwhile, downstairs, Laura's sadistic husband sneaks into the house and confronts his wife. After Ned and Laura subdue their attackers, they embrace and share a passionate kiss. Suddenly, the two apparently dead sisters recover and rush at Ned and Laura with sharp objects. However, Laura proves to be a skilled sharpshooter as she simultaneously kills Lana and Lola with two pistols, but blowing out Ned's eardrums when she fired the guns close to his head.

In the final scene, Laura and Ned propose marriage and spend their first night together, as the pet skunk watches from his hiding spot in the dresser.