The film opens with a captivating voice-over introduction by Yuri Orlov, a Ukrainian-American gunrunner, who reflects on the staggering reality of over 550 million firearms being available globally, which means one gun per every twelve people on Earth. He ponders the question of how to arm the remaining eleven individuals. The opening credits are set against the backdrop of the Buffalo Springfield song "For What It's Worth," illustrating the journey of a 7.62×39mm bullet from its inception at a Soviet Union weapons factory, through its global distribution to an African war-zone, where it is inserted into the magazine of an AK-47 and ultimately fired at a child soldier.
As the story unfolds in the early 1980s, Yuri finds himself in a Brighton Beach restaurant, where he witnesses a Russian mobster eliminate two potential assassins. This shocking event ignites his ambition to enter the arms trade, drawing a parallel between the incessant demand for weapons and the universal human need for food. He contacts an Israeli operative at his father's synagogue and acquires an illegal Uzi, marking his entry into the world of gun running. Following his first successful transaction, Yuri persuades his brother Vitaly to join him in this lucrative venture, which leads them to abandon their roles at the family restaurant.
Yuri's significant breakthrough occurs during the 1982 Lebanon War, where he manages to sell arms to every faction involved, all while bearing witness to numerous war crimes and other horrific acts. As his business flourishes in the conflict's aftermath, it attracts the attention of Interpol, particularly the idealistic agent Jack Valentine (Ethan Hawke), who is motivated by a desire for glory rather than monetary gain, complicating Yuri's usual bribery tactics.
At one point, while making a sale in Colombia, a drug lord unexpectedly offers six kilos of cocaine instead of cash, and in an ensuing dispute, he shoots Yuri with one of his own guns. After initially resisting, Yuri realizes that dealing in drugs may prove more profitable than cash transactions. Meanwhile, Vitaly succumbs to addiction, depleting a full kilo, leading Yuri to check him into rehab while he continues solo. He eventually woos his childhood crush, Ava Fontaine (Bridget Moynahan), under false pretenses for a photoshoot and they marry, welcoming a son named Nikolai (Nicky).
Yuri’s second major opportunity arises with the breakup of the Soviet Union. Following Mikhail Gorbachev's resignation on Christmas Day, 1991, Yuri travels to Ukraine to illegally acquire military equipment through his uncle, a former Soviet General. His new operations extend to Africa, where he comes into contact with Andre Baptiste Sr. (Eamonn Walker), a brutal dictator who perpetuates a civil war in Liberia. During one of his supply runs into Africa, Yuri’s cargo plane is intercepted by Interpol agents, led by Valentine. However, he cleverly avoids capture by offloading the cargo to locals before Valentine arrives.
Despite being under surveillance at his home in the United States, Yuri remains untouched by law enforcement. Valentine, unable to apprehend him due to a lack of evidence, reveals Yuri’s true identity to Ava, forcing her to confront him about his illicit activities. Although Yuri promises to quit, the lucrative offer from Andre Baptiste Sr. for his arms dealing expertise proves too tempting to resist.
During a transaction in Africa, pressure mounts as a militia group, allied with Baptiste, prepares to attack a nearby refugee camp. Vitaly implores Yuri to abandon the deal after witnessing horrific violence. Yet, Yuri insists on completing the sale, realizing that turning back would mean certain death for both him and his brother. In a desperate bid to avert the crisis, Vitaly steals grenades and sabotages one of the two trucks carrying weapons, but is ultimately killed while confronting their attackers. In his final act towards his brother, Yuri tosses an inactivated grenade to one of Vitaly’s killers just before he succumbs.
Back at home, Ava discovers Yuri’s hidden stockpile and, distraught, takes their son Nick and leaves. Further estrangement follows as Yuri’s parents reject him after learning the truth about his activities. Eventually, U.S. Customs finds a bullet in Vitaly’s corpse, leading to Yuri's arrest. However, Yuri foresees a swift release as a "necessary evil," a remark highlighting how arms dealers are often overlooked in the grander scheme of international politics and warfare. He reflects on the nature of his trade, asserting that arms dealers may ultimately inherit the world due to the ongoing conflicts amongst nations. In a poignant conclusion, he advises viewers, > "Never go to war, especially with yourself."
The film closes with an enlightening on-screen note, revealing that private arms dealers provide a fraction of the trade compared to the five largest arms exporting nations – the United States, United Kingdom, Russia, France, and China – who wield significant influence as permanent members of the United Nations Security Council.
