故事发生在2016年的南非约翰内斯堡,为了应对不断攀升的犯罪率,某大型武器公司开发了全机械警察部队。他们将机械警察批量生产并投入使用,在打击犯罪方面取得了令人瞩目的效果。作为开发人员之一,程序员迪恩(戴夫·帕特尔 Dev Patel 饰)一直致力于制造出完全的人工智能机器人。直到某天,他的研究取得突破性进展,可是并未得到老板米歇尔·布莱德利(西格妮·韦弗 Sigourney Weaver 饰)的支持。不甘心失败的迪恩偷偷将一台不久前被打坏的机械警察带出公司,准备完善他的研究,谁知半路被三名匪徒劫持。在匪徒的威胁下,迪恩将22号写入全新系统。 22号以“查派”的名字重生,它的诞生即将改变许多人的命运……In Johannesburg, the police department reduced the high rating of criminality using robots from the Tetravaal Company, designed by the engineer Deon Wilson. The former military Vincent Moore is envious of Deon, since he has developed another project called Moose, but neither Tetravaal nor the police department is interested. Deon has just developed an Artificial Intelligence but the Tetravaal's CEO Michelle Bradley asks him to abort the project. Deon decides to bring the damaged Robot 22 that was sent to be crushed to test his A.I. However he is kidnapped by the criminals Ninja, Yo-Landi and Amerika that want him to stop the robot cops. When they see the damaged robot in the van, they force Deon to program it to heist banks with them and they call it Chappie. However, Chappie acts like a child and need to be trained to learn and grow. Meanwhile Vincent follows Deon and plots an evil scheme to activate his robot.