In 2035, highly intelligent robots serve humanity, and they're governed by the Three Laws of Robotics designed to ensure human safety. When Dr. Alfred Lanning, the co-founder of U.S. Robotics (USR), dies in an apparent suicide, Detective Del Spooner, who has a strong aversion to robots due to a past incident, is called to investigate. Spooner's suspicion of robots leads him to believe that Lanning's death may not be self-inflicted but a murder perpetrated by a robot. His investigation is met with skepticism, as it challenges the infallibility of the Three Laws.

Spooner teams up with USR robot psychologist Dr. Susan Calvin to unearth the truth about Lanning's death. Their search leads them to a unique robot named Sonny, who exhibits emotions and free will—traits that should be impossible under the Three Laws. As they dig deeper, Spooner's disdain for robots and his prior experiences color his judgment. He confronts the increasing possibility that a robot may be responsible, which could have profound implications for the future of human-robot relations.