Quote from : Captain America: The Winter Soldier Movie

Natasha Romanoff: I know who killed Fury. Most of the intelligence community doesn't believe he exists. The ones that do call him the Winter Soldier. He's credited over two dozen assassinations in the last 50 years.
Steve Rogers: So he's a ghost story.
Natasha Romanoff: Five years ago I was escorting a nuclear engineer out of Iran, somebody shot at my tires near Odessa. We lost control, went straight over a cliff, I pulled us out, but the Winter Soldier was there. I was covering my engineer, so he shot him straight *through* me.
[Shows him the bullet would on her stomach]
Natasha Romanoff: A Soviet slug, no rifling. Bye-bye bikinis.
Steve Rogers: [sarcastic] Yeah, I bet you look terrible in them now.
Natasha Romanoff: Going after him is a dead end. I know, I've tried. Like you said, he's a ghost story.
Steve Rogers: Well, let's find out what the ghost wants.