A female assassin is taken into custody in Russia, and Eve and Carolyn head out to Moscow to negotiate access. She could hold the key to the organization that runs Villanelle. Meanwhile, Villanelle is smuggled into the same Russian jail.

Villanelle's mission is proving anything but straightforward, forcing her to take drastic measures. Meanwhile, Eve makes a shocking discovery, which leads her right to Villanelle and an electrifying confrontation from which neither will emerge unscathed.