"[It was] very challenging and really exciting for me because I have never had to do anything like this before," the actress told Access Hollywood on Saturday at Comic-Con in San Diego. "It's really exciting to see it all culminate to this point and really get to see the Black Widow up there on the big screen."
Scarlett said the sight of her character's costume helped her through the long hours of training and stunt work needed for the movie.
"It was many, many, hours, days, and months of stunt training and strength training, but it's fun because I had a goal," she told People. "The goal was the Lycra catsuit."
The first time she saw herself in the skin-tight get up – even she was impressed with how it turned out.
"It was crazy to see it for the first time – everything all zipped up and all the weapons in there, bracelets on, the whole look. It was pretty sweet, I have to say," she continued.
And she said the crew gave her the thumbs up when they laid eyes on her.
"Certainly walking on set, because a lot of the people that worked on the film were fans of the comic and of course they knew the Black Widow – they were all super excited to see the Black Widow," she told the mag. "When everybody in the crew were like, 'That looks awesome!' I knew. Like, 'Okay.'"
Along with her work training, "Iron Man 2" director Jon Favreau credits Scarlett's ability to give up some of her favorite foods in making the Black Widow suit look so good.
"She was wearing an unforgiving costume," Jon said. "She didn't eat much, that's for sure. She likes food, as do I, and she was definitely on a low-carb diet and training very hard. It was amazing."
Jon also noted that fans will see Scarlett in a whole new way after the "Iron Man" sequel.
"I think people are going to be very impressed when they see her," he added. "It's totally different than anything you've seen her do before."
"Iron Man 2" opens May 7, 2010.
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