This is the most dense, intricate detective/thriller movie you'll ever see. The ending gives you that "wow" feeling. But you can watch it many times even though you know the ending and get even more out of it.
This movie revolves around the question: "Who is the mysterious Keyser Soze?". It has one of the most ingenious scenarios I've ever seen. Beautiful story and great acting by Kevin Spacey, Gabriel Byrne and Pete Postlehwaite. Rewatching it is a rewarding experience.