When the U.S. government identifies Mexican drug cartels as terrorist organizations, the rules of engagement are erased. Veteran CIA operative Matt Graver Josh Brolin is unleashed with a brutal new mandate: to ignite a war between the cartels by any means necessary. He immediately recruits the enigmatic and lethal operative Alejandro Gillick Benicio Del Toro, whose personal vendetta makes him the perfect weapon for this shadow war. Their plan hinges on the kidnapping of a cartel kingpin's daughter, Isabela Reyes Isabela Moner, but the operation spirals into chaos when official policy shifts, leaving the two operatives and their young charge stranded in hostile territory. As the lines between mission and morality blur, Graver and Alejandro are forced into impossible choices that test their loyalties and their will to survive in a gritty, relentless descent into the heart of the drug war's darkness.