As in the movie "Boys' Night Out (1962) with Kim Novak", Kate, Charlie, and Luc, only know what they are supposed to want in life. They pursue their wants until they find that they really want something different than they were supposed to want. That is a lot of wants.
Lots of action, one-liners and great music (French Kiss: Original Motion Picture Soundtrack.) I notices that all the time Kate is in Paris that she just misses seeing the Eiffel Tower by a few seconds. She does find an Eiffel Tower souvenir that reminds her of Luc.
Everyone is perfect for the part. I would almost thing that Kevin Kline was French. Laurent Spielvogel plays the Concierge and has the attitude that Johnny Carson always says the French have. Even Jean Reno (birth (location) Casablanca, Morocco) seems exceedingly French.