This movie is about a man. Down and out of luck, he needs money and a mysterious man calls and offers for him the money he needs, by playing a game. In the game there are many tasks for you to complete. Each task gets you more and more money, and the gentlemen calling is watching where ever you go on security cameras; so he knows if you have completed his task. Each task also gets more graphic as you go along. I love this movie. Great story, great take. There is an American re-make of this called '13 Sins', Ron Perlman stars in it. I highly suggest watching the Thai Original first as the story line is much more uncomfortable and the tasks are a lot more daunting.