In the classic 80s comedy "When Harry Met Sally", the premise is set up by the two lead characters discussing if men and women can truly be friends due to sex getting in the way. According to the male perspective, men are always after sex thereby ruining any friendship. The female perspective is the opposite: that women are not so obsessed with sex and therefore emotions reign.
Here we have a sexy 60s film with a very similar structure, except that the point of discussion is whether infidelity happens at a physical level (sex) or an emotional one (love). The male perspective believes infidelity occurs when a person has sex outside the relationship. The female perspective insists that sex is meaningless, and infidelity occurs only if a person falls in love with someone outside the relationship.
The film wastes no time in setting up the premise and showing us how each character reacts when confronted with the reality of the situations. Having a male perspective myself, I definitely side with the dude. However, I'm sure the point of the film is to give the audience a choice. Beware: if you see this film with your wife/girlfriend/husband/boyfriend, you might want to avoid discussing it, lest one of you end up sleeping on the couch.
I have to admit that I didn't like this film at first, due to my personal opinion on the matter, but now that I've had a chance to think about it objectively (it's amazing what a night on the couch can do for a guy), I really want to watch it again.
