Detective Harry Mason has rejoined the South African Police Service after a two-year leave of absence, and moved over to the specialised Serious and Violent Crimes unit, headed by the tough and fiery veteran commander Superintendent Carl 'Blackie' Swarts. Soon afterwards, Harry is assigned to investigate the slaying of a minor politician and his family, in a township west of Johannesburg. The case, at first seemingly unsolvable, is abruptly saved by an enigmatic grassroots anarchist whom Harry befriended during the apartheid riots of the '80s, and soon the SVC is hot on the heels of one of the country's most secretive and violent vigilante groups, known as 'The Guardians', headed up by two brothers whose brutality is legendary amongst the poor inhabitants of Johannesburg's squatter camps.

As the investigation slices away at the layers of secrecy surrounding this group, other secrets surface - truths that ultimately pose a threat to Harry's unit, and to the city at large. When Harry is abruptly gunned down by unseen assassins during a dawn raid on a remote village, and a bomb is detonated in the judicial heartland of Johannesburg, his former police partner and long-time friend, Detective Jacob Tshabalala, is forced to take matters into his own hands, and expose a splinter faction of vigilantes operating within the police service itself - a faction whose connections stretch all the way into parliament itself.