Matthew Fox Slips Into His Dark Side & Tight Leather For 'Speed Racer'

LOS ANGELES, Calif. -- Matthew Fox's upcoming role of Racer X in the high-speed summer blockbuster "Speed Racer," took the actor to a dark place - and a tight one.

"He is a mass vigilante. He's wearing leather, a very tight leather driving suit that turns into sort of a helmet visor," Matthew told Access Hollywood.

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The actor said prepping for the role kept him awake at night, but not because he was working out to fill out his tight leather racing suit.

"There are a lot of ways to play a character who's shrouded in a leather suit," Matthew said. "It could go bad."

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Matthew told Access that in order to pull off outlandish costume, he went to his own dark places.

"I had just complete faith in Larry & Andy Wachowski, and Kim Baret, who designed the suit, and everybody was contributing to what [the costume] would look like within the context of the world that they were building," he said.

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The key to Racer X was literally finding the character's voice, according to Matthew.

"I worked really hard on the voice of a guy. I wanted to bring sort of a stylized thing to it," he added.

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But don't expect Matthew to slip into his trademark Racer X voice on command.

"I can't do it if I don't have the suit. The suit is what does it. Drop the helmet on, suddenly the voice is there," Matthew said.

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Catch Matthew and Emile Hirsch (if you can) in "Speed Racer," which zooms into theaters on May 9.