In a future society, time-travel exists, but it's only available on the black market. When the mob wants to eliminate someone, it sends the target into the past, where a hit man known as a looper lies in wait to finish the job. Joe (Joseph Gordon-Levitt) is one such hired gun, and he does his job well - until the day his bosses decide to "close the loop" and send Joe's future self back in time to be killed.