A Korean body swap thriller. Bridging the gap between Freaky Friday and Face/Off. It's a dramatic thriller, so most of the conflict comes in the form of mind games and verbal sparring. Surprisingly, the medical aspects weren't so outrageous as to detract from enjoyment. For once, not going into detail proved to be a bonus. Both actors do an amazing job at mimicking each other. Given their age difference it isn't the easiest task, but it's simple to spot the nuances that each performer has inherited. There's nothing too exciting after a while. Keeping it's feet on the ground means it avoids ridiculous action like Face/Off, or big comedy moments. Characters do what you yourself would do and make the same mistakes you would. Interesting and wonderfully made. The sets are little worlds all of their own. A great thriller. I wouldn't be surprised to see a remake very soon.