Mexico, 1979. Danny (Jason Statham) and his mentor Hunter (Robert De Niro) are mercenaries lying in wait for their prey. A convoy of police escorts and limousines appear. With ruthless efficiency Danny assassinates his target. But in the same car is a ten-year-old boy. Danny cannot bring himself to kill the boy, and in his moment of hesitancy is himself shot. Hunter saves his life, but Danny realizes he can no longer live the life of an assassin for hire.

Meanwhile, a political situation which will have far-reaching consequences is brewing.  British Intelligence has been drawn into a furtive and unholy alliance with Sheikh Amr bin Issa, a renegade Omani chieftain with six months to live. In exchange for oil rights, the Sheikh wants revenge on the men who killed three of his four sons—blood for blood. The twist? All three sons were killed by the SAS during the secret Oman War. The Sheikh wants a filmed confession from each SAS soldier before the execution. One final requirement: for the sake of secrecy, the deaths must appear accidental.

A Machiavellian puppet master known as the “Agent” contacts Hunter, who is now operating alone, and informs him that there is a $6 million dollar contract waiting for him in Oman if he wants the job. Once Hunter gets to Oman and realizes the SAS is the target of the hit, he tries to flee, but is caught and returned to the Sheikh’s palace where he is held captive.

In the year since the events in Mexico, Danny has been searching for peace and a new life away from the deep shadows of his past as a contract operative. This search has led him to the Australian bush where he meets Anne (Yvonne Strahovski), who owns the ranch next to his.

Danny’s new life abruptly changes when the Agent sends a photo of Hunter being held captive in the Sheikh’s palace. It is all part of the Agent’s plan: only by threatening Hunter can he lure Danny, the best operative in the world, back into the game. To save Hunter’s life, Danny must take on Hunter’s contract to kill three of the best of the SAS.

Stepping reluctantly back into the game of death he now despises, Danny pulls together the rest of his old team: Davies (Dominic Purcell), a wisecracking ex-Paratrooper, and Meier (Aden Young), an American techno-geek.