While the plot may flop and seem like a letdown at the last minute, this movie is an excellent example of showing a constant rigid atmosphere amongst the four main casts. The whole plot is greatly assisted by the understanding of Japanese and Korea's long-strained relationship, thus creating such an event.
Needless to say, if you want to feel the atmosphere of hatred (despite the small amount) from Korean people against Japan, this is perfect for you (plus a tidbit of history, yeaaah!!).