Natasha Romanoff is an agent of S.H.I.E.L.D. and a recurring member of the Avengers.
Her real name is Natasha Romanova. Not much is said about her in the movie, but in the comic books is known that she grew up in the U.S.S.R. and was trained by the Black Widow Ops program.
Black Widow was created by Stan Lee and Don Rico, and first drawn by Don Heck in Tales of Suspense. Her first appearance was as an enemy of Iron Man in 1964. The screen adaptation was in charge of screenplay writer Justin Theroux for the movie Iron Man 2.
In Iron Man 2 she uses the alias Natalie Rushman to infiltrate Stark Industries and inform Nick Fury of all of Stark's activities. Fury has become increasingly concerned over the physical and mental health of Tony Stark.
Under the cover of an assistant from the legal department, she gains proximity to Tony Stark and Pepper Potts and is able to occasionally offer Stark some advice. When Fury meets with Stark, Natasha reveals her true identity to him, however she remains undercover to Pepper Potts.
In the final scene of the movie Nick Fury tells Tony Stark that although Black Widow felt Iron Man would be a great addition to the team, she thought Tony Stark lacked the necessary emotional stability.
She is a very determined, and smart agent. While entering in a Hammer Facility she shows great skill in hand to hand non-lethal combat as well as a very competent knowledge in computers. She is also an expert in developing Psych profiles and because of it, SHIELD put her in charge of developing one for Tony Stark.
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