Single White Female (1992)

Single White Female is a 1992 American psychological erotic thriller film based on John Lutz's 1990 novel SWF Seeks Same. It stars Bridget Fonda and Jennifer Jason Leigh and was directed by Barbet Schroeder.

Allison "Allie" Jones is a software designer in New York City, engaged to Sam Rawson. Sam's ex-wife calls, and it is revealed that he slept with her recently. Allie throws Sam out, breaking off their engagement, and is comforted by neighbor Graham Knox, an aspiring actor. The next morning, Allie attends a business lunch with Mitchell Myerson, a fashion house owner looking to buy Allie's revolutionary new program. He manipulates her into significantly reducing the price; as he is her first and only client, she accepts.

Allie advertises for a new roommate to share her apartment in the Ansonia. She settles on Hedra Carlson, whom she nicknames "Hedy", and they become friends. Hedy explains that her twin was stillborn, leaving her with constant loneliness. Hedy becomes overly protective of Allie, erasing Sam's voice-mail asking Allie for a reconciliation. She buys a puppy named Buddy to bond with Allie, but becomes jealous when Sam wins Allie back and they seek a new apartment for themselves. Perceiving Allie as having rejected her, Hedy is upset and becomes further frustrated when Buddy does not come to her even when she coaxes him. Allie and Sam later find Buddy's blooded corpse on the ground underneath her apartment's window. Returning to the apartment, Allie sees that the window was open with a gap that Buddy could get through. Hedy says that Buddy's death was a mistake because she had thought that the bars outside the window had been fixed.

Mitchell attempts to coerce Allie into performing fellatio on him on completion of their deal, threatening to warn off future clients and not pay her, but she fights back and escapes. To comfort Allie, Hedy takes her to get a haircut, but after Hedy appears dressed exactly like her, including her haircut, Allie is unnerved. That night, Allie follows Hedy to an underground nightclub and witnesses Hedy passing herself off as Allie. Allie finds a shoebox containing letters addressed to Ellen Besch – Hedy's real name – along with a letter from Sam to Allie, and a newspaper clipping on the accidental drowning of Hedy's twin sister when she was nine years old.

While Allie tells Graham the truth about Hedy, they are unaware Hedy is listening. Allie leaves, and Hedy attacks Graham. When Sam returns the following night, Hedy impersonates Allie and performs oral sex on him. She begs him to leave Allie alone, but he refuses and insists on telling Allie the truth. Furious, Hedy kills him by gouging his eye with her stiletto heel.

Hedy tells Allie she is about to leave. Allie sees a news report on Sam's death and realizes what has happened. She tries to leave, but Hedy takes her hostage at gunpoint, explaining that everyone will believe Allie killed Sam. To "protect" Allie, Hedy tries to convince her that they must run away. Allie attempts to send a distress message, but Hedy catches her.

Mitchell notices his files being erased (a security program initiated by late payments), and rushes to find Allie. He finds her bound and gagged, and briefly incapacitates Hedy but is then shot by Hedy whilst attempted to free Allie. She attempts to persuade Allie to commit suicide via drug overdose, but Allie resists. Hedy points the gun at Allie as she tries to run, begging Allie not to leave her. Allie coldly tells her, "I'm not like your sister, Hedy. Not anymore. I'm like you now." Graham regains consciousness and assists Allie. Allie drags Hedy off her friend, flees, and is shot in the shoulder by Hedy. After seemingly strangling Allie to death, Hedy drags her towards the incinerator, but Allie recovers and escapes. Screaming for Allie to come out, Hedy lashes out at a mirror inside a closet. Allie stabs her in the back, and they struggle before Allie watches in horror and sadness as Hedy dies.

In an epilogue, Allie narrates that she has finally moved on. She forgives Hedy for killing Sam, and tries to forgive herself for Hedy's death, stating that Hedy's survivor's guilt was her downfall. The film finishes with a photo that is half of Allie and half of Hedy.