Marly Krushkhova arrives in Brussels for a job interview with Josef Virek, a wealthy collector. She is destitute and self-conscious, still reeling from a scandal in which her lover, Alain, used her Paris gallery to sell a forged Jospeh Cornell box to a wealthy buyer named Gnass. Marly is innocent but has been publicly disgraced. At the Galerie Duperey, the receptionist informs her that Virek is not physically present but will conduct the interview via a sensory link.

When Marly touches a designated doorknob, she is transported into a photorealistic simulation of Barcelona’s Park Güell. There, she meets Virek, who reveals he has been confined to a life-support vat for over a decade. The simulation is powered by new Maas biochips. Virek demonstrates detailed knowledge of her life and explains that he bought off both Gnass and the police after the forgery scandal.

A child named Paco—whom Virek explains is a “subprogram”—presents Marly with a piece of art: a wooden box containing a bird bone, circuit boards, a smooth white sphere of baked clay, a fragment of lace, and a piece of human wrist bone with a burnt biomonitor. Virek explains that although the piece resembles Cornell’s work, it was made by a contemporary, unknown artist. He has found seven such pieces. He hires Marly to find the maker, offering her a salary, unlimited credit, and a job lasting the rest of her life. The simulation ends, returning Marly to the Brussels gallery.

Bobby Newmark, a teenage hacker who calls himself Count Zero, attempts his first professional cyberspace run. He targets a database suggested by his contact, Two-a-Day, and rents an icebreaker (software to bypass security programs) from the same dealer. The run goes catastrophically wrong when the target’s defenses trap him with lethal feedback, overriding his autonomic nervous system. His hand trembles centimeters from the disconnect, but he cannot move.

As his heart stops, a mysterious entity reaches for him across cyberspace. Bobby perceives it as a girl with brown hair and dark eyes, surrounded by stars and wind. The entity tells him that the trap is merely a trick and then somehow frees him from the feedback loop. The shock throws Bobby from his chair, tearing the electrodes from his forehead and disconnecting him from the deck that connects him to the matrix. He hits his head on his mother’s entertainment console and passes out.

Turner and Conroy arrive by helicopter at a derelict oil rig off the Mexican coast, the staging point for the Mitchell extraction. Inside, Turner finds a technical team, including Oakey, a man who worked with him on a previous operation in Marrakech. Conroy shows Turner the mission hardware: two Maas-Neotek cyberspace decks with technology so advanced that Hosaka cannot reverse-engineer the chips. Conroy explains that the console operators, Jaylene Slide and Ramirez, and Turner’s custom Smith & Wesson revolver were all procured through Turner’s own agent.

Loading the weapon, Turner suddenly points it at Conroy’s face and demands to know why Hosaka specifically wants him for this extraction. He pulls the trigger, but the hammer clicks on an empty chamber. Conroy confirms that it is Turner’s operation now. He then reveals that Mitchell is in a Maas Biolabs arcology (buildings or structures which contain self-sustaining ecosystems) in the Arizona desert, deep within satellite-surveillance footprints. Mitchell will escape on his own and the team will help to extract him. Conroy gives Turner a gray “Microsoft” (computer chip) containing a dossier on Mitchell, compiled by an AI. Turner jacks it into his neural socket and is overwhelmed by a nauseating, nonlinear flood of intimate data about Mitchell’s entire life. The experience creates an unwanted feeling of obsessive connection to the target. Oakey tells Turner that it is time to inspect the extraction team.

Using her new line of credit, Marly checks into a luxurious Brussels hotel after a shopping spree. Her room overlooks the avenue with actual opening windows. She discards her old favorite jacket, recognizing it now as something for the cleaners. Taking a bath, she contemplates the alienating power of vast wealth and decides to go to Paris tomorrow to have her hair cut.

A courier from the Galerie Duperey delivers a package that contains a Braun holoprojector and seven “holofiche” tabs. She accesses the first fiche, and a museum-quality hologram of the box from Virek’s simulation appears above the projector. She is captivated by the arrangement of objects and notes that the piece evokes Jospeh Cornell’s work by arranging seemingly random objects to achieve a specific emotional effect. As she admires the visuals, Marly realizes that even though she told no one where she was staying, the Galerie still managed to find her and deliver the package.

Bobby wakes eight hours after his near-death experience in cyberspace. Disoriented, he showers and tries to recall what happened, retaining only fragments: a vast presence and the impression of a girl among stars. Noticing that his deck is still jacked in, he realizes the database operators will have traced his physical address. Panicking, he grabs the deck, the cash he keeps hidden in a screwdriver handle, and his gravity knife, then flees.

Bobby searches for Two-a-Day, the dealer who rented him the icebreaker software and selected the supposedly safe target. He goes to Leon’s, a pirate club that broadcasts stolen kino (films) and simstim, but Two-a-Day is not there. Leon, the proprietor, is unhelpful. Bobby waits in a loading bay, watching scavenger children retrieve a biohazard canister from a dumpster.

After 90 minutes, he returns to Leon’s, now crowded with Gothicks (a youth subculture defined by their pallor, black-lacquered hair, and surgical modifications). His inquiries are fruitless. Hungry and afraid to use his credit chip because it would reveal his location, Bobby passes a news kiosk and sees a report of a bombing at his apartment building. Realizing that he was the target, he runs.

Turner and Conroy arrive via hovercraft at an abandoned shopping mall in the Arizona desert. The site houses a nine-person extraction team and a Hosaka medical team with a portable neurosurgery pod; they were smuggled onsite inside a tanker that faked a breakdown. Turner questions their location within Maas Biolabs’ satellite-surveillance footprint. He insists on acquiring a jump-jet for the extraction, which he will pilot by jacking directly into its control system. Conroy leaves to procure the aircraft.

Turner walks toward the ruins and is struck by a memory of the desolate Mexican hotel, feeling a sense of emptiness and terminated time. He finds the three-person point team, which includes Sutcliffe, an Australian who was on the opposing side during a previous operation in Marrakech; Lynch; and Webber. They brief him on their setup, which involves a secure landline for communications, and they also explain how the rest of the team filtered in from the oil rig. Turner asserts his authority, noting that his command now supersedes Conroy’s earlier orders.

While Lynch shows him the medical pod, Turner interrogates him, suspecting that he is Conroy’s secret observer. Lynch denies this, but Turner concludes he is lying. At dusk, Webber gives Turner his revolver in a shoulder holster. As night falls, Turner sees Ramirez, the onsite console operator. Troubled by images from the Mitchell dossier, Turner knows that he will not sleep.