the idea be not original . if you have see such kind of story before and you would know what the end would come out after watch for the first twenty minute . the script and the positioning of the actor and the screening be too obvious . if you haven not see such story before and it be definitely a good experience and you will enjoy the twist at the end . do not forget to watch it again after you know the truth and you will even more enjoy the plot . even though i have a right guess at the very beginning and i still couldn not help stick on my seat till the end . conclusion represent a must see . this one from korea be well than any recent movie of the genre from japan . forget hollywood . don not miss it .