Black Widow: 8 Characters That Should Appear

8. Madame B.

You'd be forgiven if you don't remember who Madame B. is. Aside from a brief appearance as part of Natasha's Wanda-induced illusions during Avengers: Age of Ultron, she hasn't been seen anywhere else in the MCU.

That said, we learned that she was a Red Room leader, one of the trainers responsible for turning Natasha - and all the other girls - into lethal assassins. If the new film is going to explore more of Nat's past and the machinations of the Red Room, it feels thoroughly logical that Madame B. would have to turn up, at least in flashbacks, considering the role she played in Nat's origins.

Even better, it would give actress Julie Delpy - certainly best known to many for her work in Richard Linklater's Before trilogy - the chance to do more in the franchise than just be restricted to a cameo.