In present-day Washington D.C., recluse CIA analyst Ana Hernandez learns that an eastern European country is experiencing political unrest following an election that has been rigged by using fake news. The country’s defense minister and initiator of the misinformation campaign, General Velkoff, plans to buy a highly effective missile to use against the peaceful protesters but is unable to get it due to sanctions. Ana realizes that his ex-wife Mariya could travel abroad to buy this weapon and smuggle it back into the country, and she decides to report her suspicion to her superior. To Ana’s surprise, she gets sent to Zurich to talk with a journalist to find out more about Mariya’s dealings. Finding nothing that helps her case, Ana is just about to leave Switzerland when she bumps into CIA field agent Steve Barnes who is following a weapons dealer and associate of Mariya named Victor Caroli. Noticing that their cases might be linked, Ana joins Steve’s team, and together they go undercover at a fashion show in Milan that Mariya and Victor are supposed to attend. On-site, Ana strikes up a conversation with Mariya and subsequently gets invited to her yacht. At the same time, Steve’s team finds a note with Mariya’s instruction to Victor to steal the missile in Hamburg.
Ana, who suffers from panic attacks whenever confronted with open water, gets anxiety medication and boards the yacht in Portofino where she meets hacker Min Xiao who has studied with Mariya’s son Nikita at MIT. Later that evening, Ana and Mariya discuss the art of war only to be interrupted by Mariya’s lover who accuses her of being involved in her husband’s plan to violently put an end to the protests in their home country. As Mariya gets distracted Ana sneaks into her cabin and finds childhood photos of Mariya with her deceased sister. Meanwhile, Steve chases a suspect missile seller across Hamburg, only to find him to be innocent. Ana and Steve reconvene in St. Tropez where she gets a call from the journalist claiming to have found important information about Mariya’s past. Ana, Steve, and the team travel to Amsterdam to meet the journalist, only to coincidentally find Mariya and Nikita at the same event. The journalist reveals that Mariya used to be a member of the liberal party and was sent undercover to Velkoff, who was already a high-ranking military member at that time, to assassinate him. Suddenly the journalist gets shot by Nikita. Ana pursues him through Amsterdam’s canals until she suffers a panic attack as he jumps on a boat to flee. The team picks her up, and Ana sees the note they found in Milan. She correctly deciphers it to be a meeting date, leading them to travel to Blackpool where they find Victor and Mariya.
Steve follows Victor onto the Blackpool Tower where they engage in a vertigo-inducing fight until Steve finally kills his nemesis. At the same time, Ana follows Mariya and confronts her. Mariya reveals that she infiltrated Velkoff’s office under her dead sister’s name, but then cut ties with her liberal roots when she fell in love with him. However, once he started to behave more autocratic she decided to put an end to his regime. Instead of obtaining the missile on his behalf, Mariya smuggled a computer virus that Min programmed and gave her while on the yacht, which Mariya in turn handed over to Nikita in Amsterdam. Said virus can detect and destroy manipulated data, essentially wiping out fake news from the internet which is the tinder for countless conflicts around the world. As Mariya confesses Nikita sneaks into a data center in Dublin with the help of an access key that Victor gave Mariya back in Milan. Nikita plants the virus in the system and manages to escape just as it starts spreading through the internet. Suddenly Mariya gets shot by her ex-lover seeking revenge for her supposed support of Velkoff’s regime. Ana overcomes her fears and chases him by boat until he pulls the trigger on himself, accidentally causing his boat to crash into hers. Ana falls into the water and is about to drown when Steve turns up and saves her. They travel back to the beach where Mariya dies in Ana’s arms, making her promise not to reveal Nikita’s involvement in their conspiracy against his father. Velkoff is arrested for his wrongdoings and the people in his country get to have a fair re-election. Ana is promoted to field agent and, having opened herself up to the world, finally asks Steve out.