Captain Nascimento (Wagner Moura), a BOPE (Special Police Operation Battalion) officer, is tasked with clearing the drug gangs in the slums of Rio de Janeiro before a visit from the Pope. Meanwhile, desperate to take on a safer job so that he can be closer to his pregnant wife, he trains up two young Military Police officers, Neto (Caio Junqueira) and Matias (Andre Ramiro), who are disillusioned by systematic corruption. Their relationship intensifies under the ruthless training conditions as slum violence and police brutality escalates.