Even though Johnson doesn't make time travel the focus of the narrative, he has clearly put a lot of thought into how it functions within the movie's universe, not to mention the details of the universe itself. Looper unfolds in the year 2044, when America still exists as the "United States of..." but it has definitely seen better days. Poverty and homelessness are on the rise and the once-grand skyscrapers and apartment buildings seem in need of major repair. The only individuals who seem to have a steady income are the "loopers," an army of Mob-employed assassins who carry out very specialized hits. Thirty years from now, time travel will become a reality, but the technology will be closely controlled by the big crime bosses. In order to avoid the messy complications of killing their enemies in 2074, the Mob will simply port them back to 2044, where the loopers immediately blow them away and burn the bodies, thus erasing any evidence from the timestream. One of these hitmen is Joe (Joseph Gordon-Levitt), a steely-eyed youngster who takes a little too much pleasure in his work. That changes when he experiences the dark side of his chosen profession. See, when the Mob chooses to end a looper's contract they initiate a process to "close the loop" -- sending the guy's 2074 self in time for execution. Once they've literally killed their own futures, the loopers are free to live out their remaining 30 years in style, albeit all the while knowing exactly when and how they're going to die.

Like every looper, 2044 Joe isn't given any advance warning as to when he'll be closing his loop. And when that day arrives and he finds himself staring into the eyes of 2074 Joe (played by Bruce Willis), he hesitates for a crucial second, giving his older, better-trained self the chance to fight back and make a getaway. Obviously, letting your target (especially when that target is yourself) get away is a no-no in looper culture and both versions of Joe instantly become marked men with their old crew, led by grizzled gangster, Abe (Jeff Daniels). Eventually, the two sit down for a conversation in a diner (a scene that, it must be said, seems to take its inspiration from the epic Al Pacino/Robert De Niro face-off in Heat) and the central conflict is established. Young Joe needs Old Joe dead so that he can stay alive to become Old Joe; meanwhile, Old Joe is on a mission to kill the man that will be responsible for the death of somebody he loves dearly thirty years from now -- a man who in 2044 is still a child. Since neither Joe is willing to accede to the other one's wishes, the stage is set for a battle that will have major ramifications for the future as well as the present.

If your eyes glazed over a bit while reading all that, don't worry -- it plays much more smoothly onscreen. Johnson gets much of the expository heavy lifting out of the way in the first ten minutes courtesy of some handy voiceover narration, a device that's an easy shortcut to be sure, but it does efficiently establish all the crucial particulars of how time travel works in this future. And once Young Joe and Old Joe are set on their collision course, the rest of the movie clips along nicely without any dead spots where the characters are forced to explain what's happening to the audience. The narrative itself comes to resemble its own loop, winding its way to a conclusion that also functions as a beginning. (For a movie that begins like Terminator, the final act owes a greater debt to Twelve Monkeys.) Beyond the pleasures offered by Johnson's well-paced narrative and eye for detail (one running visual motif throughout the film is his use of a single light source in several key scenes, a subtle way of suggesting that a lack of power is another one of the future's many problems), the movie also contains yet another great star turn by Gordon-Levitt, who replicates Willis's glower and smirk with such precision, he could launch a whole separate career as a celebrity impersonator. (Also deserving of praise, as usual, is Emily Blunt, whose character I left out of the plot synopsis since getting into her deal would involve giving away a big chunk of the movie.)

At the same time, Johnson does make a few missteps that for me at least keep Looper from realizing the full extent of its potential. For example, I could have down with fewer scenes involving Abe's esteem-challenged henchman, Kid Blue (Noah Segen), a bland heavy who is only kept alive to be serve as the requisite wild card in the climax. (It's a shame that this role wasn't assumed by Garret Dillahunt, who has a small part as another enforcer that briefly crosses Young Joe's path. In his brief bit of screentime, he establishes a far more compelling presence than Segen.) And while Johnson does a good job making time travel work within this universe, he lets a subplot involving telekinesis -- which a certain segment of the population has developed -- slip away from him somewhat. It's an added wrinkle to the movie that feels as though it could be exploited in more interesting ways. And again, in the final moments, I was hoping for one more time travel related twist that would change up what to me seemed like a fairly obvious conclusion. Regardless of these minor quibbles, Looper remains one of the year's most enjoyable major studio releases. It's just a shame that a smart, thoughtful movie like this is all too often the exception to mainstream sci/fi action fare rather than the rule.

Click here to read our Q&A with Rian Johnson
Click here to see our do's and don'ts for time travel movies

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