Therefor I am not going to spoil the story for you. I'm not even going to touch the subject of genre (you can read that here on IMDb if you really want to though). But I will tell you this: If you are an avid fan of cinema and specifically of Korean cinema, than you might remember a movie that had a similar theme, but handled the whole thing better. That is not to say that this is a bad movie. Quite the opposite, this is quite good and has its moments.
The actors are good, the effects are good too (for a low budget movie). The story is kinda predictable, the dialogue is good too (especially the last sentence that our female protagonist hears is terrific). The mentioned sentence was something the filmmakers had to fight for (producers didn't seem to like it, but believe me, it worked with the Frightfest audience!).