A little girl named Cady lost her parents in a car accident, her aunt decided to become a guardian for her niece. Gemma sees the difficult psychological state of Cady and decides to introduce her to her project - a humanoid robot on the Android platform called M3GAN. The girl gets used to being friends with AI, and they become best friends. When M3GAN experiences a programming error, Gemma realizes that her project is broken and doesn't listen to absolutely anyone's instructions. M3GAN comes to the defense of her new girlfriend, up to the murder of the people around her.