"Basic Instinct" is a provocative psychological thriller filled with twists and turns. The film is centered around a gripping murder investigation that is tangled with sexual obsession and mind games.
The story opens with a brutal murder of a retired rock star, Johnny Boz, who is stabbed to death with an ice pick during sex. The details of the crime scene closely mirror a murder described in a novel written by a beautiful and enigmatic crime novelist, Catherine Tramell (Sharon Stone), making her the prime suspect.
Detective Nick Curran (Michael Douglas) is assigned to the case. Curran is a troubled cop with a history of alcohol and drug abuse, as well as violent tendencies. Despite the possible dangers and his own vulnerabilities, Curran gets drawn into a complex relationship with Tramell, a master manipulator. Tramell becomes the main suspect, yet she has a rock-solid alibi and plays mind games that entangle everyone around her, leaving no room for concrete evidence.
Throughout the investigation, another potential suspect surfaces - Catherine's jealous and possessive girlfriend, Roxy (Leilani Sarelle). Meanwhile, Curran's psychiatrist, Dr. Beth Garner (Jeanne Tripplehorn), who also happens to be his ex-lover, becomes entangled in the investigation as some clues start pointing towards her.
As the plot unfolds, the boundary between the truth and deception blurs. The tormented Curran succumbs to Tramell's seductive games, initiating a steamy affair with her, further complicating his ability to stay objective in his investigation. The psychological intensity of the story heightens when it's revealed that one of Tramell's novels outlines a plot suspiciously similar to the predicaments that Curran finds himself in - the story of a detective who falls for the wrong woman and gets killed.
The narrative is loaded with suspense, providing alternate leads and suspicions to keep the viewer guessing. In a climactic scene, Roxy attempts to kill Nick out of jealousy, but dies in the process. This event doesn't stop Catherine, who continues her mind games.
In the film's ambiguous ending, Curran and Catherine end up together in bed, and as they're about to make love, Catherine reaches under the bed, where earlier, Curran found an ice pick. The screen then cuts to black, leaving the viewer in suspense about what transpires next.
"Basic Instinct" is renowned for its intense eroticism, convoluted plot, and unforgettable characters, making it a landmark film of the '90s neo-noir genre.