Looper is one of the few time travel fables that didn’t have me scratching my head in utter confusion. Writer/director Rian Johnson doesn’t bog his story down with the same complex technicalities that make most time travel movies more perplexing than entertaining; somehow, he takes a radical idea and reduces it into layman’s terms, thus allowing non-sci-fi audiences like me the chance to understand what’s going on and why. Because I didn’t have to expend all my mental energy on theoretical logistics – and given my lack of an advanced degree in physics, that wouldn’t get me very far anyway – I could better concentrate on the other aspects of the story, all of which are highly engaging, if a little dark. Here is a film that combines a thought-provoking social commentary with a thrilling action extravaganza.

Taking place in a crime- and poverty-stricken Kansas City, the story is set in 2044, when a segment of the population has developed telekinetic powers and the invention of time travel is still thirty years away. At that future date, time travel has been made illegal and is used in secret exclusively by crime syndicates; they send a target back to 2044, and a special assassin called a looper takes the target out and disposes of the body. A looper is paid in bricks of silver, which are stashed in a sack worn by the target. When a looper’s contract expires, the target is sent with gold bricks rather than silver. The looper, who is now no longer obligated to kill anyone, can live out his life for the next thirty years. But when his time comes, he must be sent back to 2044 and be assassinated. This is a delicate operation, and there can be absolutely no loose ends, not even if your target happens to be yourself.

We meet a looper named Joseph Simmons (Joseph Gordon-Levitt), who doubles as the narrator and kills all his targets in the middle of a desolate cornfield. An expert at what he does, he has become cold, elusive, and fatalistic. He makes frequent trips to a local club and spends time with his favorite showgirl (Piper Perabo), although he’s usually numb on a drug that’s dropped into the eyes like Visine. His life in complicated when his future self (Bruce Willis) manages to escape assassination after being sent back to 2044; although it’s obvious that the senior Joseph is looking to change the past, I will refrain from disclosing the reason why. Let it suffice to say that he’s looking to prevent something from happening, and in order to do that, he must prevent something else from happening first.

One part of this mission involves the junior Joseph entering the lives of Sara (Emily Blunt) and her young son, Cid (Pierce Gagnon), both of whom live alone in an isolated farmhouse. Sara is fiercely protective of Cid, never hesitating to threaten trespassers off her property with her loaded shotgun. The more Sara and Joseph learn of their respective situations, the more inclined they are to help each other. This is despite the fact that neither one of them is completely forthcoming – at least, not initially. We quickly realize just how above average Cid is; he’s articulate, perceptive, mechanically competent, and remarkably intelligent. But he’s also a child, and therefore capable of reacting immaturely to specific situations he doesn’t have a full understanding of. I cannot be more specific than that. Rest assured, the senior Joseph is on his way over. So too are several other loopers, including the passionate but incompetent Kid Blue (Noah Segan).

Levitt, who has recently made his mark on films as diverse as (500) Days of Summer, Inception, Elektra Luxx, Hesher, and Premium Rush, yet again shows his ability to seamlessly transition from one role to the next. As Joseph, he dramatically sets himself apart from his other characters with only the subtlest of changes, namely a distortion of his face. With just a slight frown and deeply furrowed brows, he alters his appearance to the point where we know it’s him and yet still notice that something is different. He looks and behaves uncannily like a hardboiled private eye – disparaging, unemotional, accepting of his own fate and uninterested in anyone else’s. And yet his encounters with Sara and Cid prove that he isn’t as detached as he thought he was. This isn’t love so much as a sudden need to make things right.

Although Looper is a winner on levels of narrative, structure, theme, and performance, it will undoubtedly push boundaries with its unflinching depictions of children being shot. One shooting isn’t actually seen, but the audience is made well aware of what’s happening. Another ends with a graphic slow motion shot of a bullet grazing a child’s cheek, letting loose a quick spurt of blood. These scenes are contextually “effective,” but that doesn’t mean I enjoyed watching them. The argument, I suppose, is that I wasn’t supposed to enjoy it, that the intention was to shock and disturb me. Perhaps. Nevertheless, there are lines I personally don’t like seeing crossed, and this is one of them. Take that into consideration when buying a ticket for this movie. Not everyone is likely to be as understanding.