After the terrorist attacks on 9/11, Jack Ryan (Pine), studying at the London School of Economics, becomes a U.S. Marine second lieutenant fighting in Afghanistan, where his spine is critically injured when his helicopter is shot down. During a lengthy recovery, he attracts the attention of Cathy Muller (Knightley), the medical student helping him learn to walk again, and Thomas Harper (Costner), an official with the CIA who recruits him. Ten years later, Ryan is working on Wall Street covertly for the CIA looking for suspect financial transactions that would indicate terrorist activity. When the Russian Federation loses a key vote before the United Nations, Ryan notices that the markets do not respond in the expected way. He discovers that trillions of dollars held by Russian organizations have disappeared. A large number of these funds are controlled by Viktor Cherevin (Branagh), a Russian tycoon. Ryan’s employer conducts business with Cherevin, so when Ryan discovers certain accounts are inaccessible to him as an auditor, he has reason to visit Moscow and investigate. On arrival he narrowly survives a murder attempt by an assassin (Anozie) posing as his bodyguard. Ryan sends an SOS and is surprised to learn his backup is Harper. During their debrief, Ryan explains how Cherevin’s shadow investments could make the United States vulnerable to complete financial collapse following a staged terrorist attack, which would also weaken global markets. At his meeting with Cherevin the next day, he is told that the problem company and all of its assets have been sold, thus preventing Ryan’s audit. Meanwhile, Muller, now Ryan’s fiancée, concerned he may be having an affair, secretly flies to Moscow to meet him. Against protocol for unmarried couples, Ryan reveals that he works for the CIA, to her great relief. Improvising on the situation, Harper has Muller agree to be included in a plan to infiltrate Cherevin’s offices. Ryan and Muller meet Cherevin at an upscale restaurant across the street from Cherevin’s office. Over dinner, Ryan causes a scene and purposely insults Muller. Excusing himself, he gains access to Cherevin’s office where he downloads critical corruption files. Ryan and the CIA discover Cherevin used a falsified death certificate to place his son, Aleksandr (Utgoff), in the United States as a sleeper agent. Ryan uses his talent for pattern recognition to locate Aleksandr’s hideout and intended target, Wall Street. He locates a fake police response vehicle driven by Aleksandr and gives chase. After Ryan catches up and engages in a physical confrontation with Aleksandr, he discovers the bomb in the rear of the police decoy. Unable to defuse it, he hijacks the vehicle with Aleksandr in it. He later crashes it into the East River while simultaneously jumping out, as the bomb detonates, killing Aleksandr. Cherevin is executed by his co-conspirators in Russia. Ryan and Harper are called to the White House to brief the president.