When Natasha Romanoff discovers she's pregnant she uses a lengthy mission to cover it up and gives the baby to an orphanage so the child can live a normal life. The Red Room adopts Vanya Romanova pressing her through torturous training. Now Vanya's the Black Mamba of HYDRA. When she discovers S.H.I.E.L.D. will she continue on a path of destruction or will she change her alliances?

The Red Room produces the greatest assassins in history. The Winter Soldier is brought in to train the Black Widows, and Natalia Romanova quickly comes to his attention. After both are punished for humanizing the perfect weapon, they meet again outside of Odessa as enemies. Years later, Natasha helps Steve Rogers rehabilitate his best friend and must discover what he remembers.