Scarlett Johansson explains how 'Captain America 2: The Winter Soldier' differs from 'Iron Man 2'

Scarlett Johansson made her first appearance in the Marvel Cinematic Universe as Natasha Romanoff/Black Widow in Iron Man 2 in 2010. She then starred in The Avengers in 2012 and will reprise her role yet again in Captain America: The Winter Soldier aka Captain America 2 when the film hits theaters on April 4.

Johansson sat down with The Huffington Post to talk about her new partnership with SodaStream and the Spike Jonze film Her and her Marvel roles came up during the course of the conversation. The site asked her how Cap 2 differed from Iron Man 2, and here's how the 29-year-old actress responded:

"My first Marvel film was Iron Man 2 and then we did The Avengers and then Chris Evans and I did Cap 2, but I think that film, there's a couple of new characters. The Falcon [played by Anthony Mackie] is a new character in that, and of course Sebastian Stan is kind of continuing his character, obviously he's playing the Winter Soldier. But these characters really kind of take on something bigger than they've ever seen, so I think it's something that they can't do without each other. In that sense, we were in it, kind of neck-and-neck, and it's a bigger responsibility. But then again, even in 'Avengers 2,' we all play in it, it's not like, 'Great, I'll be booking, like, two days a week and then be eating sandwiches the rest of the week.' No, it's on. We all are fighting in it together, we're all fighting our own battles and our own demons and it's a lot of dramatic work, and the physical part of it, so the films all have their own challenges, but it's fun."

The Avengers: Age of Ultron will have the same ensemble cast as the first film, and some fans have wondered how Joss Whedon and company would balance the roster, which now includes even more characters. But based on Johansson's comments, it seems as though everyone involved stays busy throughout production, which should translate on screen.