After faking his death, Arthur Bishop has been living quietly in Rio de Janeiro with the name Santos. He is approached by Renee Tran, who knows of his true identity and explains her employer wishes for Bishop to kill three targets and stage them as accidents. Seeing her mercenaries waiting nearby, Bishop makes his escape, and flees the country to Thailand. He takes shelter at a resort island beach house of his friend, Mae, and learns that Tran is working for Riah Crain. Bishop and Crain were orphans that grew up together, but later sold to a gangster and trained as warriors. Bishop made his escape and left Crain behind.
Sometime later, a bruised woman, Gina Thorne, approaches Mae for first aid before returning to a boat anchored nearby. Mae observes Thorne being beaten by a man aboard the boat and alerts Bishop. Bishop and Mae rescue Thorne from the man, but in the scuffle, the man hits his head on the boat’s equipment and dies. Finding no evidence of his identity, Bishop sets the boat ablaze. While Mae tends to Thorne’s injuries, Bishop finds that Thorne is also connected to Crain, and believes Crain anticipated Bishop would become romantic with her; Crain would then have kidnapped her to make Bishop take the assassination jobs. When he charges Thorne with his theory, she reveals that Crain threatened the children’s shelter in Cambodia that she worked at unless she participated. Over the next few days, Bishop does get to know Thorne better and falls in love, but as expected, Crain’s mercenaries soon arrive and abduct the two.
Thorne is taken to Crain’s private boat, while Bishop is brought to Crain himself, where he coerces him to take the assassination jobs with Thorne’s life, providing him with the necessary resources to complete them. The first target of Bishop is a warlord named Krill, who is incarcerated in a Malaysian prison. Bishop travels to Malaysia and gets himself imprisoned to access Krill. Bishop gains Krill’s trust by killing a man already planning on killing Krill. Bishop meets with Krill and kills him and Bishop escapes the prison with the help of Crain’s operatives. The next target is Adrian Cook, who runs an underage trafficking ring from Sydney. Bishop manages to bypass the tight security of Cook’s penthouse apartment and break the glass bottom of Cook’s overhanging pool, plummeting him to his death.
While relaying details of the third target, Crain allows Bishop to speak over video to Thorne, who has arranged her setting to allow Bishop to identify the registration number of Crain’s boat. Bishop locates the boat and attempts to rescue her, but Crain has caught Thorne’s attempt in time and his mercenaries quickly stop the attempt. For his insolence, Crain demands Bishop complete the final assassination in 24 hours, identifying the target as Max Adams, an American arms dealer. While planning the attempt, Bishop recognizes that Crain’s targets were his only other major competition in arms dealing. Bishop instead approaches Adams and warns him of Crain’s plan, and gets Adams to help. Bishop fakes Adams’ death, and reports his success to Crain, who directs him to a meeting point.
There, Bishop fends off attacks by Crain’s mercenaries and makes for Crain’s boat parked nearby. He fights off more of Crain’s men and discovers the boat is rigged with explosives before rescuing Thorne, placing her in an underwater escape pod. Crain stops him before he can escape, and the two fight. Bishop overpowers him and secures him to the boat, when Crain reveals the explosives are set to go off soon. Instead of diving overboard, Bishop races into the boat, moments before the bombs explode, killing Crain and apparently Bishop.
Thorne is rescued and the remains of Crain’s boat are salvaged with no other signs of life. Adams watches the operation from afar, and sees that one of the salvaged pieces was the anchor compartment, and monitors video to see Bishop emerge from the compartment several hours later, and then deletes the video to keep Bishop’s status secret. Thorne returns to Cambodia and her teaching duties, but later is surprised when Bishop arrives a few days later.