Nina is a trainee programmer at Onisciente ("omniscient"), the company based around the system that is omniscient and controls everything in the city. Its motto is "viva sem medo" ("live without fear"). The system itself explains "it's not privacy versus safety, it's privacy and safety" because humans have no access to the system- only the main computer can analyze all the footage and information.
Most of the footage is from personal drones that look like bees. They synchronize with a person and follows them everywhere, even the bed and the shower. If a person leaves the city, the drone desynchronizes and stays behind, awaiting their return.
One day, Nina comes home to find her father, Inazio, murdered. She calls in the murder, but the system states that there have been no crimes detected in that area. Her father's drone is seen hovering nearby the dead body. Nina later explains that the victim's drone doesn't alert anyone, but the culprit's should have triggered the system.
Police officers eventually arrive and talk with Nina and her brother. In the crime scene interview, the police officer says that the city's investigative structure was dismantled 15 years ago, because the system does it all and the system never fails. Nina asks her boss for help - to view the footage of her father's drone - but they can't access the system's footage. With the help of a friend, Nina becomes determined to get access to the drone's footage in order to find her father's murderer. She must get biometric access to enter the main control room in order to find the drone footage. She also has to avoid being seen by her own drone while doing this.