What makes this film great is the script and the acting. Both are top notch and just as important is that all the characters fit well together and suit the actors. Very well cast.
When locations change, you're presented with a postcard style display to indicate this and provide you information as to this destination.
Very enjoyable and each scene is a complement and continuation of the last. There are no abstract or dream states which I think audiences always find difficult to understand what the producer/director is trying to convey.
The writing is great and the script includes some good comedy (wit). Each character has their fair share of funny remarks, and there are no annoying / trying to be the comic relief, characters in the movie (examples of these types of characters would be Jo Pesci in Lethal Weapon or Chris Tucker in Rush Hour).
Usually in any movie there are bound to be characters that you can't associate with / relate to or simply just don't like. Some of this is always to do with the actor, but primarily it's due to the script they have been given or the direction for their character. But in this movie that just doesn't seem to exist, and I found myself liking all the characters.
Each character has their own "flare" and for this movie it's almost as if their characters were written to play directly at their strengths and acting style. All the cast shine and yet at the same time don't overshadow or dominate the others.
The plot is plausible and enjoyable and the stories behind each character have been sufficiently developed.
There are no "flashbacks" used in this film. You are seeing the events as they unfold. Sure the situation may be based on past events, but they do not jump back and forth in the time line, so the story is easy to follow but still has a few small surprises.
The scene of Bruce Willis exiting the police car, I think deserves a special mention as it looked awesome and unique.