In the year 2035, humanoid robots serve humanity, which is protected by the Three Laws of Robotics of Isaac Asimov. Del Spooner, a homicide detective in the Chicago Police Department, has come to hate and distrust robots after a robot rescued him from a car crash while allowing a 12-year-old girl to drown, based purely on cold logic and odds of survival. When Dr. Alfred Lanning, co-founder of U.S. Robotics (USR), falls to his death from his office window, a message he left behind requests Spooner be assigned to the case. The police declare the death a suicide, but Spooner is skeptical, and Lawrence Robertson, the CEO and other co-founders of USR, reluctantly allows him to investigate.