It’s been nearly 20 years since Joseph Gordon-Levitt starred as an alien trapped in a suburban kid’s body on 3rd Rock from the Sun. Since then, his acting roles have run the gamut—from indie films to blockbusters—but 2012 may well be hailed as the year he officially arrived. He’s held his own in Dark Knight Rises, helmed the action chase film Premium Rush and did his best Magic Mike impersonation on last week’s Saturday Night Live. Daniel Day-Lewis even personally requested him to play his son in Lincoln out later this year. (“That was a real honor. He’s such a phenomenon,” Gordon-Levitt says.)
But first, Gordon-Levitt’s highly anticipated sci-fi thriller Looper hits theaters on Sept. 28. The 31-year-old actor took a few minutes out of his whirlwind schedule to sit down with TIME and talk Looper, face-changing makeup and what he wants to work on next.
TIME: You play a hit man assigned to kill your future self. What questions did you have when you read Rian Johnson’s script?
JOSEPH GORDON-LEVITT: Most people ask, ‘so did you guys spend a lot of time talking about how the time travel is going to work?’ and we didn’t because, to be honest, the time travel is really simple in Looper. Instead, we talked a lot about the character, and I think what we spent most of our time discussing how we were going to convince the audience that Bruce and I were playing the same guy 30 years apart.
You originally wanted to play both parts.
I did suggest that at one point. It sounded like an intriguing idea: ‘Hey I can do this. It’d be great. It will be all me!’ If you quote me there you have to write that I was being sarcastic.
(READ: TIME’s review of Dark Knight Rises)
Of course! But after Bruce Willis was cast, the special effects master worked his magic to make you appear like his younger self. Much ink has been spilled about the prosthetics you wear to accomplish this…
I wore prosthetic makeup one other time and [Looper special makeup effects artist] Kazuhiro Tsuji did that makeup too—in G.I. Joe. But then I played this crazy cartoonish villain, which is a kind of trippy because it’s not realistic at all. But this time around, to look in the mirror and see something that is quite realistic and yet just a bit different from my own face, is a really bizarre experience and inspiring as an actor. I get inspired when I put on the right shoes or the right jacket. It sounds superficial, but it’s true. You find some thing on the outside that you can hook on to with the character. And a new face is by far the most intense version of that that I’ve ever experienced.
There’s a terrific scene where you and Bruce Willis are seated face-to-face in a diner. Then you really look like a younger version of him.
We worked very hard at that. When you’re sitting across from each other everyone has to instantly believe that it’s the two versions of the same man. Bruce and I and Rian all kind of got out of town and just rehearsed for four days.
(READ: Richard Corliss on Gordon-Levitt in Premium Rush)
How else did you prepare to play Bruce Willis Jr.?
We would meet up and have lunch or dinner and just hang out and talk. That was probably the most productive thing was just spending time with him. I also did a bunch of other homework on my own—I watched his movies and ripped the audio off of some of them and listened to them on my iPod. Bruce recorded himself doing some of my voiceover monologues, and he sent me those so that I could hear what he sounded like.
You first worked with director Rian Johnson on 2005’s Brick. What’s the difference between working together then and now?
We’re both older and wiser. But I think the similarities are more striking than the differences. When we were making Brick we had no idea whether anybody was going to go see that movie at all. We just really thought it was cool, and so we did it. I think the same goes for Looper. Even though it’s a bigger movie and Bruce Willis is in it, and we know lots of people are going to see it, we kind of just maintained that same attitude of ‘this is just cool.’
The little boy in Looper, Rian Gagnon, is around the same age as you were when you started acting. Do you have any advice for him?
I remember when I was his age I didn’t like it when people would sort of be didactic with me. I felt like saying, ‘Hey I have to do this just as you all have to do this so treat me like the same as everybody—an actor, a professional, because I’m being professional.’ And Pierce was professional, and I would just treat him as such. Any advice I’d give I’d probably give more to his mom. She talks to him about the material as an artist, not as some mindless sapling, which is good. But I would definitely recommend school—not homeschooling.
(READ: Corliss’s tribute to Joseph Gordon-Levitt in 50/50)
If you were to meet up with yourself 30 years from now, what would you say to yourself?
I do think that’s one of the central ideas of the movie—what would it be like to talk to your future self or your past self. For me, the conversation would be quite one sided. I would really just want to listen. I’m really grateful for what I’m getting to do right now in that I get to work on projects that inspire me and work with people that I care about and trust, and I hope that I have continued to do that—and that I don’t have to try to kill myself.
Speaking of inspiring projects, you’re about to make your directorial debut with Don Jon’s Addiction, where you star as a porn addict alongside Scarlett Johansson and Julianne Moore. Have you learned anything from the directors you’ve worked with in the past few years?
Absolutely. Innumerable knowledge I think was imparted. It wasn’t so much ‘let me sit you down an teach you something,’ but just by watching Rian [Johnson] and Chris [Nolan, director of Dark Knight Rises] and Steven [Spielberg, director of Lincoln] was enormously helpful. Working with those three guys in the last year was a big part of what emboldened me to give directing a try.
Anything else you’d like to try in the future?
I would love to do a musical. One day I’ll find the right one.
MORE: TIME on Joseph Gordon-Levitt in (500) Days of Summer