TORONTO -- Actor Joseph Gordon-Levitt says he loves to completely transform himself when he takes on a film role.
In the time-travel thriller "Looper" -- which kicked off the Toronto International Film Festival on Thursday -- he got the chance to undergo a rather unusual metamorphosis, turning himself into "Die Hard" star Bruce Willis.
Well, sort of.
In the sci-fi thriller, about hitmen tasked with killing thugs sent back in time, the two actors portray the same character, but at different points in life.
"What I like best in acting is becoming something very different from myself and the story in 'Looper' represents a unique challenge in that regard," Gordon-Levitt said Thursday in an interview.
"There's one guy: the young version and the old version. That poses a very intriguing challenge, how can I transform myself such that the audience, without an instant of hesitation, just understands that I'm the same person as this guy."
In the film, Willis represents Gordon-Levitt's future self, 30 years down the road. Gordon-Levitt sat in a makeup chair for three hours on each day of shooting and studied the sound of Willis's voice and his body language in preparation for the part.
The duo rehearsed extensively to match up their mannerisms and Willis complimented Gordon-Levitt on his impression, likening him to a magician.
"Sci-fi films are like magic tricks. At some point you have to let go of it and just believe you're in the story. I was so surprised the magic trick we were trying to do works," Willis told reporters at a festival news conference Thursday.
He wasn't the only one who gave Gordon-Levitt's performance the thumbs up.
"Looper" co-star Emily Blunt -- who plays a mother who reluctantly takes in Gordon-Levitt's character -- was wowed by the dedication of the "Dark Knight Rises" and "Premium Rush" actor.
"He was very much in the makeup -- and I mean that in the sense that he was that guy during the day," she said during an interview.
"He really embodied Bruce, he really managed to find his sort of essence without it being a cheap impersonation and I think that's a real gift."
This is the second year in a row Gordon-Levitt has appeared at the festival; he received kudos last year for his turn in the cancer comedy "50/50."
Willis, meanwhile, also praised director "Looper" Rian Johnson ("The Brothers Bloom") for conjuring up a futuristic world and yet still creating believable relationships between characters.
"There are reminders the whole way that we're in a different time situation but it's a real emotional film," said Willis.
The stars of "Looper" were set to walk the red carpet Thursday night and the film is due to open in theatres Sept. 28.
Earning the opening film nod was a huge thrill for Johnson, who had 20 family members from Kansas, Los Angeles and New York in town for the premiere.
"This is a big deal for me, I'm excited, man," said a giddy Johnson in an interview.
"Our hair was blown back when they offered it to us. For me, Toronto has a perception, rightly so, of being just a movie-loving town.
"To have the world premiere be in front of a crowd that's really a crowd of cinephiles, in a town that hosts this festival because it loves film, that's really exciting to me. I can't think of a better crowd to show the movie to first, I'm really psyched to be in that room."
The Toronto International Film Festival runs until Sept. 16.
