In a futuristic gangland, a killer (Joseph Gordon-Levitt) works for a mob in the year 2042 as a "Looper", where he kills and disposes of people who are sent from the year 2072. Loopers like himself are well paid on the terms that the target must never escape. When one target arrives however he recognizes the victim (Bruce Willis) as himself and hesitates, allowing his older self to escape. The resulting failure of his job causes the mob to come after him, forcing him to fight for his life as he hunts his older self.