10Different: Black Widow
Without her own solo movie at the time, Black Widow was given a supporting role in this film. Though Steve Rogers was obviously the main character, this gave audiences the chance to learn a little bit more about Natasha and give the character a little more depth.
Black Widow is not
featured in the comic book run and it is one of the ways in which the movie gets the upper hand. Scarlett Johansson and Chris Evans have great chemistry together and she was the perfect person to go on this journey with him.