In a not-so-distant future, life in Johannesburg is disrupted by the arrival of a spaceship that lands on Earth, brought by an alien race known as the "the settlers." However, instead of integrating and sharing their advanced technology, these extraterrestrials end up living in inhumane conditions in a segregated area of the city called District 9, where they are treated like pariahs and outcasts. The story focuses on Wikus van de Merwe, a bureaucrat from the MNU corporation who is assigned to lead the operation to evict the aliens and relocate the survivors to a more distant concentration camp.
During one of the excavations, Wikus becomes exposed to a mysterious alien fluid, triggering a surprising and terrifying transformation: he begins to acquire the abilities of the aliens. As he becomes the target of his own company and the government, he is forced to seek help from an alien named Christopher, who is trying to return to his home. As the situation intensifies, Wikus must confront his own humanity and make difficult decisions in a world where ethics become blurred. Caught between two worlds, his journey becomes a social critique of xenophobia and exploitation, exposing the darkest truths of human nature and its relationship with the other.