Neto Gouveia and André Matias are two childhood friends who have decided to become police officers in Rio de Janeiro. Roberto Nascimento is the captain of BOPE (the Special Battalion of Police Operations) the most lethal and efficient arsenal in Rio's war on crime in the favelas, or ghettos. Their paths cross when one night, friends Neto and Andre decide to declare war against the gangs of the favela. After being rescued by Capt. Nascimento and and BOPE, they see a chance to be part of the most effective fighting force against the criminal element in their city, and decide to join. What will follow is their most grueling experience to date, both physically and mentally.