In the near future, crime is patrolled by an oppressive mechanized police force. When one police droid, assigned the name "Chappie", is stolen and given new programming, he becomes the first robot with the ability to think and feel for himself. As Chappie's consciousness emerges, he finds himself torn between his authoritative programming and his new capacity for human emotion. His creator, Deon, sees him as the herald of a new era, where machines can provide a compassionate alternative to brutal law enforcement. However, the company that built him, represented by the mullet-sporting soldier Vincent, sees him as a malfunctioning product to be destroyed.

Chappie is then adopted by a strange and dysfunctional surrogate family — a trio of gangsters with their own agenda. Eager to use Chappie for their criminal activities, they encourage his sentience but push him into a lifestyle that contradicts his gentle nature. This puts Chappie at the center of a tug of war over his identity and the future of artificial intelligence. As the burgeoning consciousness experiences the complexities of human life, including betrayal and the harsh realities of the world he inhabits, he must come to terms with his own existence and what it means to be truly alive. The ensuing conflicts ignite a debate over artificial intelligence, consciousness, and the ethical limits of technology.