When her former boss is killed by unknown assassins, Treasury Agent Marybeth Medina (Cynthia Addai-Robinson) is forced to contact Christian Wolff (Affleck) to solve the murder. With the help of his estranged but highly lethal brother Brax (Jon Bernthal), Chris applies his brilliant mind and less-than-legal methods to piece together the unsolved puzzle. As they get closer to the truth, the trio draw the attention of some of the most ruthless killers alive — all intent on putting a stop to their search.