You must see 13 Tzameti if you like thriller movies. I just watched it with a friend last night and I'm still thinking about it.
Gist of the movie is about a young man that gets involved playing a game that he knew nothing about because he was posing as someone else. He thought their would be tons of money in it for him, but he didn't realize what the game was about.
Watch the trailer it will show you how intense the film is.