That's the first word that comes to mind when Mr. and Mrs. Smith is mentioned. The perfect example of what and action/comedy movie should be. Effortlessly cool, brilliantly witty. Brad Pitt is by far the only actor on the planet who can make being an idiot look so cool.
Where to start. Well plot wise it's functional, as functional as you need it to be for this kind of movie. the action set-pieces are great, but what surprised me is the subtle and not so subtle metaphors for the types of problems every realtionship goes through. This movie is simply perfect in that it achieves exactly what it set out to do and more. If you want to analyse a movie to death and question the human condition go and see something else. If you want an exceptional piece of entertainment, then this is the film for you. Enough character development is given to make the characters more than two dimensional without diminishing from the overall action and comedy. The dinner scene where John and Jane both know each other are hitmen but not sure if the other knows that they know is fantastic.
I haven't been this entertained by a film since Pirates of the Caribbean. It's not Citizen Kane, but for what it set out to do it is nigh on perfect.