Exclusive: ‘Looper’ trailer reveals Joseph Gordon-Levitt’s transformation into young Bruce Willis

Joe (Joseph Gordon-Levitt) is a "looper," a hit man who eliminates targets sent back in time by organized criminals in the future. He makes sure that whoever appears in front of him ends up dead, even when that person is himself from 30 years in the future (Bruce Willis).

That's the set-up for "Looper," a mind-bending action thriller from writer/director Rian Johnson ("Brick," "The Brothers Bloom"). It's a risky premise, mostly because the audience has to believe that Gordon-Levitt and Willis are actually the same person. And as Johnson admitted to me in a phone interview, "that was tricky because they look nothing alike."

So how did this odd pairing come about? According to Johnson, he's been developing the idea for nearly a decade, and he brought it up to Gordon-Levitt when they were promoting his debut film "Brick" at the Sundance Film Festival in 2005. So the intention was always for Gordon-Levitt to play the young version, but he said, "I had no idea who is going to play the older guy until we really got into the casting process."

[Photos: Gordon-Levitt and Willis in 'Looper' photos]

Johnson revealed that Bruce Willis was the first actor he approached to play the part, and he quickly signed on for the role. However, that's when the real work began. Johnson said, "Bruce was perfect for the part in so many ways, but that was one big challenge, the physical differences between them." He wanted to avoid trying to completely change Gordon-Levitt's appearance and instead "take a couple key facial features and tweak them, just to give the audience something to grab on to."

The task of changing Gordon-Levitt's look went to makeup designer Kazuhiro Tsuji, who had previously worked with the actor on "G.I. Joe: The Rise of Cobra." Johnson said that Tsuji started by taking casts of both Gordon-Levitt's and Willis' faces, and then "he started sculpting clay onto this perfect model of Joe's face." The process of finding the correct balance of facial features took several months, and Gordon-Levitt ended up spending three hours a day in the makeup chair getting the prosthetics applied.

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To perfectly capture Willis' voice, Gordon-Levitt stated at Wondercon last March that he recorded dialogue from movies like "Sin City" and would listen to the tracks repeatedly on his iPod. Johnson said that Willis helped out as well: "He recorded some of the monologues that Joe was going to have in the movie... so that Joe could listen to that and actually practice it with the actual lines."

Beyond dinner together before filming, Johnson said Willis and Gordon-Levitt did not have much interaction prior to filming. And that was helpful, he feels, for the scene featured in the trailer where the young and old versions face off in a diner. Johnson said, "I think in the way that they eye each other, there should be something a little bit uncanny for Bruce about seeing himself sitting across the table. And I think that comes across."

You can see for yourself just how thoroughly Joseph Gordon-Levitt's transformed into Bruce Willis when "Looper" pops into theaters on September 28.

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