In modern-day Russia, Dominika Egorova is a famed Russian ballerina who supports her ill mother. Following a career-ending injury, Dominika is approached by her uncle, Ivan, who works in Russian intelligence. She is tasked with seducing Dimitry Ustinov, a Russian politician, in exchange for her mother’s continued medical care. As Ustinov rapes her, he is killed by Simionov, a Russian operative authorized by Ivan. Ivan offers Dominika a choice to begin working for Russian intelligence, or be executed so there are no witnesses.
Nate Nash is a CIA operative working in Moscow. While meeting with an asset in Gorky Park, they are confronted by the police. Nash creates a diversion to ensure his asset, a mole in Russian ranks code-named Marble, escapes detection. Nash is reassigned back to the U.S. but insists that he is the only individual whom Marble will work with. Since he cannot return to Russia, he is assigned to Budapest, where he will regain contact with Marble.
Dominika is sent to train to become a Russian operative, known as a ‘Sparrow’, capable of seducing her targets. Dominika excels in her training, despite some friction with her trainers, and she is assigned to Budapest. Russian SVR has been tracking Nash, and hopes to find out the identity of Marble. Dominika’s assignment is to gain the trust of Nash, and reveal his contact.
Upon her arrival in Budapest, Dominika lives with Marta, another Sparrow. Dominika quickly makes contact with Nash, who correctly determines that she is a Russian intelligence operative. Dominika reveals her true identity to him, as well as her motive to find out Marble’s identity. While Marta is out, Dominika inspects her room, and realizes that she is working to gather information from Stephanie Boucher, a chief of staff for a U.S. Senator. Dominika realizes she needs more time, and claims to her uncle that she is helping in Marta’s effort to gather information from Boucher. Upon returning home one day, Dominika finds Marta brutally tortured and murdered. Simionov reveals that he carried out the murder as a warning not to betray Russian secrets.