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Joseph Gordon-Levitt, Emily Blunt and Bruce Willis premiered their new time-travel thriller Looper at the Toronto International Film Festival Thursday night, and the stars weighed in what they'd do if they could travel through time themselves! Watch the video…

Video: Joe & Emily are Loopy for 'Looper'

Looper, in theaters September 28, finds Gordon-Levitt is a time-traveling hit man from the future tasked with taking out the older version of himself -- played by Willis. When the mob wants to get rid of someone, they send their target 30 years into the past, where a "looper" -- a hired gun, like Joe (Gordon-Levitt) -- is waiting to mop up. Joe lives the good life with his job as a looper – until one day the mob decides to "close the loop," sending back Joe's future self (Willis) for assassination. Will he kill himself, or team up to get revenge?