'Looper' Director Rian Johnson on What Bruce Willis and Your Grandmother Have in Common (Video)

Rian Johnson, the writer-director of sci-fi action film Looper, says he didn’t have actors in mind when he wrote the film, but after he spotted Bruce Willis’ name on a list during casting, he thought that would be a great – albeit maybe impossible – fit.

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“I think he’s such a tremendous actor,” says Johnson. “And also the fact that he’s Bruce Willis and brings this sort of action-star persona worked in some very interesting ways with this character.”

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Willis plays an older version of Joseph Gordon-Levitt’s character Joe in the fast-moving, mind-bending film. Young Joe, who lives in the year 2042, is a hitman who is tasked with killing people who are sent back to him from the future. When the future version of himself shows up, however, it leads to an action-packed violent game of cat-and-mouse between the older and younger versions of Joe.

Gordon-Levitt had three-hours worth of makeup put on his face every day and also studied Willis’ cadence of speech in order to look and seem like a younger version of the action star.

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Johnson tells The Hollywood Reporter that instead of seeking out two actors who looked the same, he decided to cast the best actors for the roles, and then have Gordon-Levitt work to look like Willis.

“We all have been watching [Willis] for years and years. In almost the same way you know what your grandmother looks and sounds like, you know what Bruce Willis looks and sounds like,” explains Johnson.

“And I said, 'Let’s use that instead of fighting it. Let’s give that to Joe and let him use that to grab on to,'” he says.

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Johnson says that one of the biggest challenges of the writing process was figuring out how much explanation the audience would need about how time travel worked and what the future looked like in general.

“I was constantly surprised through the process with editing how onboard the audience was and how savvy,” he says adding that he had filmed a lot more explanation that ended up getting cut during editing because the audience didn’t need it.

“They were making the leap and they were just going with these characters and that was a really cool thing to discover,” he says.

Looper opens in theaters on Friday, Sept. 28.

Watch THR’s interview with Johnson above.

Email: Rebecca.Ford@thr.com; Twitter: @Beccamford