The film is set in a world between humans and chimps. As a result of human scientific experiments, the intelligence of orangutans has been greatly improved, and they begin to wake up and fight against human domination, fighting for freedom and living space.

In the future world, humans and alien insects have a fierce conflict. In order to defend the earth and expand the universe colonies, human beings formed a huge star river team to go to the alien battlefield and insects to launch a life-and-death struggle.

The story takes place in a future scrap town, a world made of steel and garbage. Alita, a mechanical girl, was found and repaired in the junkyard by Dr. Ed, after which she launched a series of adventures in this cruel world with her strong fighting ability and kind heart, and also uncovered the secrets of her own life and the huge conspiracy hidden behind it.

A ship full of alien refugees appears above Earth and docks in Johannesburg, South Africa. The humans have set up Zone Nine in this area to keep the alien refugees isolated here. With the passage of time, the contradiction between humans and aliens gradually escalates, and a conflict about survival, power and morality is inevitable.