FleshEatingZipper says: "As a kid who grew up on Star Trek, I know first-hand the benefits and pitfalls of a time travel plot. Trek was often light-hearted about its implementation, almost to the point of using it as a silly contrivance, but other forms of the fiction dare to be more adventurous. If investigated too deeply, time travel can truly bury the audience in mind-****ery. The most drastic point I can think of would be Shane Carruth’s ultra-indie flick Primer, in which the time you spend inside the time machine translates to how far back in time you go. That film explores how one manages paradoxes and the multitude of timelines you create when you make multiple trips, which is havoc for something as elegant as a narrative. While not quite the brain freeze that Primer was, thankfully, Looper engages that kind of deep, exploratory time travel with incredible flare and gobs of delicious violence."