Two allegedly American gals, with thick Serbian accents, not too long out of college go on aquatic related vacation in Serbia, they do this despite the fact that one of them has serious issues with swimming and the sea in general. They meet up with an old boyfriend, who is now engaged to a sleazy looking local woman, and sparks still fly between the guy and one of the 'American' gals. Everybody makes nice, drinks, gets drunk, a few of them have sex, regret it, and they all change into swim wear and go off to an island that used to be a Nazi concentration camp. Yes, you heard that right, an island in the ocean off Serbia was a Nazi concentration camp. Yes, I know, it boggles the mind.
Once on this island they encounter a murderous old dude and a mermaid. And she's a shape changing mermaid who can go back and forth between being a hot mermaid to a scaly fish looking creature with a mouth full of scary looking teeth. Of course most everyone dies before the hottest of the 'American' gals gets rescued.
The whole thing is pretty preposterous. From the American girls who speak with heavy Serbian accents, to the idea that the Nazis would make an idyllic island off a beautiful coat a concentration camp, to the shape changing mermaid, to the...oh fuck it, it's just all bad. And it's not bad in a 'it's so bad it's good!' way, it's bad in a 'it's painful to watch these women with uni brows try to act sexy and act like they're not Serbian and why did they bother wasting so much money on this stupid shit' way.
Seriously, it's pretty atrocious. It makes you wish the Croats had been better armed during the wars that took place in the wake of the break up of the country formerly known as Yugoslavia.