Duplicity is not a great film nor is it a bad film. It's mostly entertaining, but easily forgettable which is exactly what I expected.
1. Plot twists - is it really a plot twist when you are expecting a plot twist? Well, it's obviously clear from the trailer that it is a "trust no one" "nothing is as it seems" kind of film. It delivers the twists well, I actually didn't know how it would end except that it would probably not end how I expected. It did tend to drag toward the middle and the constant reminder that the two main characters can't be trusted became tedious.
2. Great chemistry - Julia Roberts and Clive Owen already proved to have chemistry in Closer. They proved their status as Hollywood royalty plus they aren't bad to look at...
3. Fantastic performances from Tom Wilkinson & Paul Giamatti- They both deliver some much needed humor to the film.
4. Quick witted, smart and sleek style - The film was like a spy version of Oceans 11, just not as satisfying, because it lacks depth. Plus while Oceans 11 had us rooting for the bad guys, this film didn't really have bad guys (or good guys for that matter). It did have some zingy one-liners though.