As the city of Los Angeles shimmers below, a limousine snakes along Mulholland Dr. Stopping suddenly, the driver turns around, trains a gun on the passenger, a sultry, raven-haired woman, and orders her to get out. At that moment, a pair of drag racing cars screams around a curve, smashing head on into the limousine. The woman, dazed, crawls out of the wreckage and stumbles down to the city streets below. Exhausted from her ordeal, she takes refuge in some bushes outside a stunning Spanish courtyard apartment building and falls asleep. The next morning, she is awakened when Ruth, one of the tenants, walks past to meet a waiting cab. After loading her luggage into the trunk, Ruth returns to her apartment to fetch her keys and the woman sneaks in, hides under a table and falls asleep. At Winkie’s coffee shop nearby, a man recounts two nightmares he had about a horrific man who lurks in back. As the man and his companion go to investigate, a hideous tramp appears from the rear of the building, causing the man to faint. Soon after, fresh-faced, young Betty Elms from Deep River Ontario, lands at the Los Angeles airport, filled with dreams of becoming an actress. An elderly couple whom Betty had befriended on the flight wish her “all the luck in the world,” then climb into the back of a limousine and drive off, grinning from ear to ear. Betty then takes a cab to the courtyard apartment owned by her Aunt Ruth, who has agreed to let her stay while she is away on business. There Betty is greeted by the complex’s eccentric manager, Coco Lanois, who speaks in aphorisms. As Betty peruses the apartment, she is startled to see a woman’s cocktail dress and purse discarded on the bedroom floor. In the bathroom, Betty finds the naked raven-haired woman standing in the shower. Assuming that the woman is a friend of her aunt’s, Betty asks her name. The woman, now suffering from amnesia, gazes vacantly at a poster of Rita Hayworth from the film Gilda , and says her name is Rita. At the Ryan Entertainment office in downtown Los Angeles, Adam Kesher, a self-important, petulant young film director, meets with his backers, the sinister Luigi and Vincenzo Castigliane. As Mr. Roque, a wheelchair-bound dwarf, views the meeting over closed circuit television, Vincenzo extracts a publicity photo of actress Camilla Rhodes from his briefcase and demands that Adam cast her as the lead in his new film. After Adam vehemently refuses, Vincenzo menacingly states “it’s no longer your film.” Defiantly storming out of the building, Adam goes to the Castiglianes’ limousine and smashes it with a golf club. Roque, who communicates only through a cellphone headset, then mumbles into the headset, causing Adam’s production to be shut down. In a seedy office, a scruffy blonde man and a man seated at the desk laugh about a car accident. Reaching for a black book on the desk, the blonde pulls out a gun and shoots his companion. One of his bullets goes astray, however, and hits a corpulent woman in the next office. While the blonde wrestles with the woman, a janitor appears, forcing the blonde man to shoot both the woman and the janitor. The janitor falls, hitting the switch on his vacuum cleaner, and when the machine springs to life, the blonde blasts it with his gun, starting a fire that sets off the alarm, sending the inept killer fleeing out a window. After Aunt Ruth telephones, Betty learns that Rita is an uninvited guest. When Betty gently asks Rita who she is, Rita breaks into tears and admits that she does not know. Betty then presses Rita to search her purse for identification, but when Rita unzips the bag she finds it is stuffed with $100 bills and an oddly shaped blue key. After Rita suddenly recalls that she was on her way to Mulholland Drive, Betty make an anonymous call to the police from a pay phone outside Winkie’s and discovers that there was an automobile accident on Mulholland Drive the previous evening. Upon learning that his film has been shut down, Adam unexpectedly returns home and finds his wife Lorraine in bed with Gene, the pool man. In retaliation, Adam douses Lorraine’s jewelry with paint, after which the feisty Lorraine pounces on him, then orders him to get out after Gene slugs him in the face. At Winkie’s, Betty is scouring the newspaper for a story about the accident on Mulholland Drive when a waitress wearing the name tag “Diane” approaches their table. The name jars Rita’s memory, and after she tells Betty that the name “Diane Selwyn” seems familiar, Betty looks it up in the phone book. After leaving his house, Adam seeks refuge in a run-down skid row hotel. When the manager informs Adam that some men have called the hotel looking for him, Adam, sensing danger, phones his assistant, who delivers a message from a man named Cowboy, instructing Adam to meet him at a corral at the top of Beachwood Canyon. At the corral, a flickering light announces the arrival of Cowboy, a man with a chalky complexion wearing a ten gallon hat. After telling Adam to hold an audition after which he will proclaim that Camilla Rhodes “is the girl,” Cowboy cryptically adds that Adam will see him “one more time if he does good, two more times if he does bad.” The next day, Betty rehearses a scene with Rita, then drives to an audition on a grungy set where she meets washed up producer Wally Brown and aging lothario Woody Katz, the production’s leading man. After giving a steamy performance, Betty impresses chic casting director Linney James who insists that Betty accompany her to Adam’s set. There, Adam is auditioning a nondescript blonde named Camilla Rhodes. After uttering that Camilla “is the girl,” Adam sees Betty. When their eyes lock, Betty remembers that she has a date with Rita and runs off. Rita and Betty take a cab to the address listed as Diane’s apartment, and when Betty’s knock at the door goes unanswered, Betty climbs in through the window and opens the door for Rita. When they see a woman’s rotting dead body sprawled across the bed, Rita realizes that she is in grave danger and runs screaming from the apartment. Back at Aunt Ruth’s, Rita is about to cut off her long hair when Betty stops her and gives her a blonde wig to wear as a disguise. Rita dons the wig, and the two women admire their blonde, bobbed hair images in the mirror. That night, after Rita and Betty make passionate love, Rita awakens, calling out “silencio.” Rita then asks Betty to accompany her, and they drive through deserted downtown streets to the Club Silencio, a theater dedicated to exposing the artifice of illusion. There, they are transfixed as a woman on stage lip syncs the song “Llorando” (“Crying”) acapella. When the woman collapses onstage and is carried off, the song continues, and Betty, moved to tears by the performance, reaches into her purse for a handkerchief and finds a steely blue cube inside. Rita and Betty rush back to the apartment, where Rita goes to retrieve the purse that she has hidden in the closet. When she returns carrying the blue key, Betty is gone. After Rita inserts the key into the cube, it opens and falls out of Rita’s hands onto the rug. Some time later, Ruth returns and finds the apartment eerily empty, and the box missing. When Cowboy cracks open the door of Diane’s darkened apartment and says “hey pretty girl, time to wake up,” Diane awakens to find a blue key on her coffee table. Diane’s neighbor then comes to inform her that two police detectives have been looking for her. After the neighbor leaves, Diane turns from the window and imagines a smiling Camilla standing in the room. While Diane makes a pot of coffee, she turns around and she sees the bare-breasted Camilla lying across the couch. As Diane fondles Camilla’s breasts, Camilla grows cold and ends their relationship. [While watching Adam and Camilla rehearse a love scene on the set of Adam’s new film, Diane realizes that they are having an affair.] Diane angrily throws Camilla out, then furiously masturbates. Some time later, Camilla phones Diane to tell her a limousine is waiting to drive her to a party. As the limousine winds down Mulholland Dr., the driver suddenly stops and Camilla appears to escort Diane to the party at Adam’s house. After Adam introduces Diane to his caustic mother Coco, Adam and Camilla exchange knowing glances and toast to love. Over dinner, Diane tells Coco that she came to Los Angeles from Ontario after winning a jitterbug contest and that she and Camilla met while auditioning for the same part. After Camilla won the role and went on to become a star, she arranged for the struggling Diane to perform bit parts in her pictures. Adam stops nuzzling Camilla to boast that he got the pool and his wife got the pool man in their divorce settlement, then announces that he and Camilla are engaged. Extremely distraught, Diane crashes her place setting to the floor. Some time later at Winkie’s, a bedraggled Diane hires the scruffy blonde man to kill Camilla. After she hands him a case stuffed with cash, the man holds up a blue key and says she will get it when the job is done. In back of Winkie’s one night, the tramp shoves the blue box into a crumpled paper bag and drops it to the ground. A diminutive elderly couple, laughing hysterically, then scramble out of the bag. Back at her apartment, Diane glumly stares into the distance past the blue key, which is now on the table. Suddenly, the elderly couple squeezes under the door, grow to life size and drive Diane into her bedroom with their accusatory shrieks. Diane cowers under the covers, pulls a gun from her nightstand and shoots herself. At the Club Silencio, a lone woman sitting in an opera box whispers “silencio.”