The main problem with this film is the lack of chemistry between the two principals who never convince that there is any true feeling between them. The script is also to blame since they never get to say anything to each other but meaningless snippets of dialogue. Compare with the masterly "Before Sunrise" and "Before Sunset" where you believe in those characters and in their mutual affection.

The party scenes were also lame (the Japanese seem to be a cool breed and yet we, the audience, never were allowed to enter to enter their world as the main characters patently did) and the one joke ("hey let's take the p*ss out of the Japs!!") soon began to tire and appear quite offensive.

The hypocrisy of the leads characters (being sweet to their spouses while angling for sex) was also a great turnoff (as if was not for me in "Before Sunset") simply because we are never given the chance to feel any warmth for this pair of insomniacs.

All in all a good idea badly executed.