OK, the title already gives away the entire story: two couples are swinging. Yeah, but it's...complicated. These are not just thrill-seeking strangers, they are best friends. The guys work together, the families live on the same street, next to each other, two of their teenage children are dating. We're talking about people who are extremely comfortable with each other and who have probably thought about doing that for many years. One day, the guys go on a work trip on a semi-deserted island in the Caribbean and decide to bring their wives along. Once they settle in a cottage together, the guys start talking about swinging and decide to go ahead and do it. One of the wives (the more "liberal" one) is easily convinced, but the other is a church-going type, and it takes some time before she accepts it. But eventually she does and we're then left to assume that they keep doing that for the entire "vacation." Before they come back, however, they swear that it was just a "holiday" and they will never do it again. But once they get back in the Czech Republic, they simply can't help it and keep doing it. Until the entire families discover the truth. And their reaction is probably one of the best thing about this movie, because the writing and the acting are very sincere. We've seen this situation in other movies, but here's the twist in this one: it doesn't end bad. No one gets "punished" for violating the religion-inspired society rules and eventually pretty much everyone accepts it, although some of the family members are still disturbed. There's no judgment and no blame here. It just happened because it was bound to, and there's nothing really wrong with it.The ending is a surprise and I'm not going to spoil it for you, it's just the final touch of humor that will have you chuckle while the final credits roll.While this is no masterpiece and looks a lot like your typical no-budget indie movie (especially to us Americans), it's a genuinely sweet and honest comedy that shies away from Hollywood conventions. The religious right will no doubt hate it, and yet I'm pretty sure that situations like this are very common among them. Just not openly and sincerely like it happens in this movie, because keeping the appearance of a healthy marriage among the square religious types is more important than anything. And when something like that comes to the light, it's always some atheist liberal's fault...Yes, there is nudity (not more than your average European movie...) but the sex is definitely "PG", as in more hinted than actually shown. So I would have no problem letting teenagers watch this movie.