which black widow comics feature the story mentioned in the movie avengers assemble?

Hello there.
I'm wondering if someone is able to please help me.
I watched the avengers movie the other week and I really liked the whole background story about the black widow and hawkeye saving her from when she was evil. I know there hasn't been a film released about this story before so assume that it must be featured in comic form and was wondering firstly if I. Am correct and secondly over which comics?
Sorry if I'm sounding like a noob here but just thought if I don't ask I'll never know and would like to know what comics so that i can read the story
Many thanks for your time
Matt