Looper was marketed as a time-traveling sci-fi action adventure. What the movie was actually about though, was a character study of what influences people as they grow up. What turned a child into Joe the amoral assassin? What turned the assassin into the vengeful old man? What turned Cid into a terrible warlord? What person or event might have changed the course of their lives? The movie was much for of a philosophical discussion than a sci-fi adventure, and so was not what most people were expecting.
Yeah, I went in with only the knowledge that time travel was involved. I was pleased with the film overall. I try not to have too many expectations. I take things for what they are. That might make it seem like I'll give dreck more of a pass, but I don't mind. I feel that as long as the internal universe is consistent, I can give it a chance.