'Avengers': S.H.I.E.L.D. Helicarrier Is 'Crazy,' Says Star

There are so many major superheroic players involved in Joss Whedon's "Avengers" that it's easy to forget about the equally important supporting characters in the film. Like S.H.I.E.L.D. agent Maria Hill (played by "How I Met Your Mother" actress Cobie Smulders) for example.

Thanks to a lengthy chat with Smulders at D23, we are very intrigued about Hill's story arc in the film, but also psyched that Smulders snagged the role. She's just so fun and down to earth, and didn't geek out too much when we asked her about the most surreal moment on set thus far.

"I showed up to the set, like a week before we started shooting, just to meet with Joss and do rehearsals and stuff and I walked on the set and it was freakin' huge," Smulders recalled of stepping onto the S.H.I.E.L.D. helicarrier for the first time. "It was the size of a soundstage, then you walked up these steps and you were just surrounded by this amazing gorgeous set, which my character is in charge of running. I was like, 'Holy smokes, this is crazy and this is big.'"

"You hear that all these people are in it and it's a huge movie and it's got this budget, but when you're there on the set, there is like a thousand people," she marveled. "I want to say that everyday there was about 200-300 extras on this one set. It was just like, 'What?!?' So that was just kind of crazy, [I thought] 'Wow, we're really doing it.'"

We don't know quite as much about the S.H.I.E.L.D team as we do the superheroes, so we asked Smulders to shed some light on the Whedon-scripted character dynamic between Nick Fury and Agents Coulson and Hill.

"We would have conversations on set between Clark [Gregg] and I, [about] who's higher-ranking," she said. "We decided no one is a higher rank, it's just different areas of expertise. Clark is in the field a lot, like in "Thor," that kind of action, and I'm at the home base and I run stuff. Sam Jackson is our boss and oversees everything," she added. "We make all the decisions but he's a bit of a guide."

What do you think of Smulders' Agent Hill? Tell us in the comments or on Twitter!