Natasha Romanoff

Natasha Romanoff is a Russian counter intelligence agent and assassin also known as the Black Widow. She would later become a member of the Avengers.

The Red Room
She lived in a foster care home in Stalingrad when her city was bombed and attacked by Russian Separatists. She survived with her foster sister Katenka Timofey and were both recruited by a man named Ilya Fyodor for a new assassin program at the Red Room Academy where they were trained to blend in with the Western society. At some point rumors of the Sovjet Union falling apart came through and in order to preserve the project, they were moved to a different location. They continued training until finally the day of the Graduation Ceremony happened and Natasha and Katenka were sparring. When Natasha got the upperhand, she was forced to kill Katenka and passed the final test, before being carted off to a medical facility by Fyodor's men. Years later she was fully integrated in the American society and took down a target, when she noticed she was followed by a mysterious person.