Chris Hemsworth stands 6'3" tall, and he put on 20 pounds of muscle to play Marvel Comics' hero, Thor. He is equally adept at swinging his fists as he is a mythical hammer. So who in the world would actually volunteer to be punched by him?
Tom Hiddleston, his costar in "Marvel's The Avengers," is who. Hiddleston reprises the role of Loki -- first seen in last year's "Thor" -- the adopted brother of the god of thunder with an apocalyptic case of sibling rivalry. Loki assembles an army to conquer the planet, and it will take the combined strength of Earth's mightiest heroes to stop him.
Naturally, the climactic battle for the planet culminates in Thor and Loki coming to blows, and when I sat down to talk to Hiddleston, he explained that the hits you see on screen were real.
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Hiddleston said that when they were shooting the fight scene, "Joss [Whedon, the director] came over and said, 'Guys, I'm just not really buying it. You need to sell it more. You either need to hit each other harder or you need to react bigger.'" As they readied for the next take, Hiddleston took a moment to confer with Hemsworth. "I said to Chris, 'Dude, just hit me. Just hit me because I'm protected here and it's fine.' He's like, 'Are you sure?' I was like, 'Yeah, it will look great. Just go for it.'"
Cameras then started to roll, and Hiddleston said, "[Chris] really went for it and he's just pummeling me in the chest and elbowing me in the face and Joss came back after that take and went, 'We got it. It's great.'"
I asked Hemsworth about his reaction to actually hitting his costar. Hemsworth chuckled and recalled there was a moment when Hiddleston doubled over a bit when a body blow connected. He told me, "I turned to the crew and I said, 'He told me to do that! You all heard that.'"
Hiddleston did have a certain amount of protection from his elaborate costume, which weighed 30 pounds. But Hiddleston said the additional weight -- including another seven pounds for his horned helmet -- made it a real challenge to perform the fight scenes, especially in the heat of New Mexico where they shot most of the movie.
Still, Hiddleston told me he had good time throwing down against a superhero. He said, "It's fun. I love shooting action because your brain switches off. You enter almost a Zen-like state where you're just infusing choreography with emotion. It's like a dance."
"Marvel's The Avengers" opens on Friday. Watch Tom Hiddleston as Loki in a clip: