WARNING: Spoilers for Anna.
The ending of Luc Besson's Anna is filled with twists and turns as the titular Russian assassin faces off against both the CIA and the KGB to secure her personal freedom. Here's how Anna Poliatova (Sasha Luss) pulls off each of her deceptions, including her one final ruse to get out from under the thumbs of both the U.S. and Russia's spy agencies with the help of Olga (Helen Mirren), her KGB supervisor.
At the midpoint of Anna, which is set throughout 1985-1991, Anna was sent on a mission by Olga but she walked into a trap set by CIA agent Leonard Miller (Cillian Murphy). He had already suspected Anna of being the assassin of an arms dealer named Oleg (Andrew Howard) in Paris, where Anna was posing as a fashion model and Oleg's girlfriend. In fact, Anna did kill Oleg but her alibi held up when she switched places with a double, who was caught on camera fleeing the hotel where the murder took place as Anna escaped in disguise. Miller then secretly kept tabs on Anna after he interrogated her and he learned she was the KGB's best assassin. Since she had no options, Anna agreed to become a double agent for the CIA and inform them of her continued activities as a KGB operative. Anna and Miller then began a sexual relationship wherein he learned what Anna's true goal is: to escape from the KGB and create a new life for herself in Hawaii.
Miller promised he could make Anna's dream come true if she performed one job for him: assassinate Vassiliev (Eric Godon), the head of the KGB, which she agreed to do. This was a revenge plot Miller concocted because when Vassiliev took power in 1985, he had nine CIA agents stationed in Moscow murdered. Vassiliev then sent their heads in boxes to Miller at CIA headquarters in Langley, Virginia. Miller wanted the sadistic Vassiliev eliminated to restore the original rivalry and balance between the CIA and the KGB. Only Anna could get inside Vassiliev's inner sanctum at KGB headquarters - because Anna owed the old spymaster a game of chess. Unfortunately, Anna's mission to kill Vassiliev happened under the nose of Alex Tchenkov (Luke Evans), Anna's original recruiter and handler who is also her first lover.
Anna's Failed Mission Explained
When Anna assassinated Vassiliev, Alex was in the room; she drugged him as she made her escape but the toxin she used wasn't strong enough and Alex was able to hit the alarm, placing the building on red alert. Taking on scores of soldiers and guards, Anna had to fight her way out through the bowels of the KGB building but Miller, who was supposed to be her transport out of Moscow, had to leave her. Later, back in New York, Miller received a text from Anna to rendezvous in a Paris park. However, Anna had also contacted Alex and told him to meet her at that same park. Alex and Miller (and their respective agencies) found themselves face-to-face when Anna appeared with a deal for both of her lovers: Anna gave back all of the CIA information she stole from Miller and offered all of the KGB data she took from Vassiliev to Alex in exchange for her freedom. Since neither the CIA or KGB wanted the meeting to escalate to violence, Alex and Miller let Anna walk away. However, Olga shot Anna dead as she was leaving the park - or so it appeared.
Anna Faked Her Death - And Became A Triple Agent For Olga
What really happened was Olga and Anna faked Anna's death, thanks to Olga actually killing Anna's double, who she then switched places with the real Anna. The truth is Olga had always known Anna was working for the CIA because she saw marks on her wrists from when the Americans handcuffed Anna as Miller brokered their deal for her to turn. Anna, who was now a triple agent working exclusively for Olga, reported Miller's plan to assassinate Vassiliev to her - and Olga agreed to let it happen because it would mean she would replace him as head of the KGB.
So, when Anna cut her deal with Alex and Miller, Olga feigned revenge for Anna's betrayal and "murdered" the blonde-gone-rogue; but in reality, Anna switched with her dead double, changed outfits in the sewers (revealing she had shaved her head bald), and slipped away in Paris.
Olga Let Anna Escape
However, Anna sprung one final surprise for Olga when she took over as the new head of the KGB: Anna left a video asking Olga to erase her file from the KGB database. Olga could have betrayed Anna and sent the full force of the KGB after her but instead, she did as Anna asked and wiped Anna Poliatova's records completely. Because even though Olga was hard on Anna throughout her career, Anna had actually earned her respect. Olga understood Anna no longer wanted a life where she was subject to "slavery" under powerful men in the government, which is something Olga (whom Vassiliev mocked for being "ugly") could relate to. Now that she's the head of the KBG, Olga can run it as she wishes, which is her version of the freedom Anna won by escaping her life as a government assassin.