'Looper's' Joseph Gordon-Levitt on Bruce Willis' First Reaction to Acting Opposite His Younger Self (Video)

Looper star Joseph Gordon-Levitt says that when he and director Rian Johnson found out that Bruce Willis would be playing the older version of Gordon-Levitt’s character, it was “a big fist-pump moment.”

“That was followed shortly thereafter by me saying, ‘How the hell am I going to do this?’” he tells The Hollywood Reporter.

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Gordon-Levitt was tasked with playing the younger version of Joe, a looper – which is a hitman in the future who kills people sent to him from the even further away future.

The actor – who recently starred in Premium Rush and The Dark Knight Rises – spent three hours every day in the makeup chair to have his face altered to look like a young version of Willis. He also studied Willis’ cadence of speech and other qualities so he could not only look like Willis, but also sound like him.

Willis’ older version of Joe is sent back to 2042 so the younger version of Joe can kill him. This leads to an action-packed violent game of cat-and-mouse between the older and younger versions of Joe.

“My character in Looper is not exactly a hero,” Gordon-Levitt tells THR. “There aren’t really heroes or villains in Looper, and I love that. Because in real life, no one’s black or white -- everyone is some shade of grey.”

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Gordon-Levitt and Willis had their first scene together in a diner, and that’s when Gordon-Levitt got to see the action star’s first reaction to seeing his own face on someone else.

“Bruce is a really understated guy.  He doesn’t butter anybody up, he’s not a diplomat. He’s just really honest. And so when he pays a compliment, it means something,” explains Gordon-Levitt.

“So him just off handedly saying ,‘You sound like me’ was really meaningful,” he says.

Gordon-Levitt – who reteams with director Johnson for this film – may know Willis in more detail than most after this film. He shared a surprising detail about the action star with THR.

“Bruce is such a powerful presence on the screen, you would assume that he would be loud. He’s actually not loud – he’s quite soft spoken,” he says. “He doesn’t have to raise his voice. He just has a kind of innate confidence.”

Looper, which also stars Emily Blunt, opens in theaters of Friday, Sept 28.