Teenager Alejandro lives in La Zona, an enclosed, residential haven of wealth and privilege in the middle of Mexico City, surrounded by shocking poverty. In the early hours of his birthday, three kids from the slums break into one of La Zona's houses. In the robbery that follows, an old woman is killed, but her housemaid escapes and alerts the security guards. They take swift, brutal action: Two of the young intruders are shot dead. The third - Miguel - escapes and flees deeper into La Zona.