Rio de Janeiro. Brazilians call it Cidade Maravilhosa - the Marvellous City - but crime festers in its favelas like cancer.

John Milton is visiting an old friend who runs a close protection business guarding the city's elite. Milton offers to stand in when one of his bodyguards doesn’t turn up for work. The job? Take the wife and daughter of an anticorruption judge to a school recital and bring them back again. Simple?

Not so much. The girl is snatched off the street, and Milton is nearly killed. As he recovers at a Group Fifteen safe house, he decides on two objectives.

First, find the girl.

Second, punish the kidnappers for what they’ve done.

Milton’s trip becomes a lethal quest into the heart of the lawless slums and against the gangs who wield the real power in Rio. But Milton won’t stop there - he’ll chase them right into the horrific heart of darkness until his special brand of justice has been well and truly served.