Isaac Asimov's Robot City

Isaac Asimov's Robot City is a series of novels written by various authors and loosely connected to Isaac Asimov's Robot series. It takes place between The Robots of Dawn and Robots and Empire. Each volume is complete in itself, but they form a continuing series. The novels were written in response to a writing challenge issued by Asimov to write a series involving the Three Laws of Robotics, which brought about a collaboration of several authors. Asimov provided outlines for stories which filled in the gap between Asimov's own robot stories and his Foundation series, explaining the disappearance of the robots prior to the establishment of the galactic empire. Isaac Asimov's Robots and Aliens followed in this series, with the same protagonists and many other characters. The common theme of all books of both series is the interaction between the characters and autonomous cities run and populated by robots. Robot City was also released as a mystery game for the PC in 1995. The player takes the role of Derec.

Robot City

The Robot City novels begin revolving around a man who has no memory of who he was, but believes he might be called Derec after a name-badge he is wearing. Derec journeys to Robot City, a city of robots, with a handful of transient humans. There, Derec meets another mysterious person calling herself Katherine, whose real name turns out to be Ariel, and together the two disprove their role in the apparent murder of a human whose identity is not known by the robots. Fleeing an increasingly dangerous Robot City, Derec and Ariel journey to Earth to find the city's creator, the insane Dr. Avery and learn their true identities. As the series goes on, Both Ariel and Derec are repeatedly asked to confront more questions as old ones are answered, all of which, no matter how broad, always seem to connect with Robot City.
The series makes much use of the Three Laws of Robotics and their interpretations and interactions when dealing with obscure scenarios, such as levels or priority in conflicting orders, a human brain in a robot body, and do the laws apply to non-human, but sentient beings. It also addresses, in passing, differences in interpretation of the First Law, namely, the difference between physical harm and psychological harm.
Perihelion ends with a promise to "continue with Robot City # 7", which appears to refer to Changeling, the first volume of Robots and Aliens.