Isaac Asimov's I, Robot

N8-C, better known as Nate, has been Manhattan Hasbro Hospital's resident robot for more than 20 years. A prototype, humanoid in appearance, he was created to interact with people. While some staff accepted working alongside an anthropomorphic robot, Nate's very existence terrified most people, leaving the robot utilized for menial tasks and generally ignored. Until one of the hospital's physicians is found brutally murdered with Nate standing over the corpse, a blood-smeared utility bar clutched in his hand.

As designer and programmer of Nate's positronic brain, Lawrence Robertson is responsible for his creation's actions and arrested for the crime. Susan Calvin knows the Three Laws of Robotics make it impossible for Nate to harm a human being. But to prove both Nate's and Lawrence's innocence, she has to consider the possibility that someone somehow manipulated the laws to commit murder....