This one is different.

Shot in one take, the peculiar German production may surprise even the most experienced viewer. It may also evoke rather violent emotional responses. I discussed the movie with a friend and we both agreed that the way it was shot, the actors and the directing were all aiming towards a sensation of "realness", which is probably the reason why you are so engaged throughout the evolution of the plot, reacting so strongly as the story takes some unforeseen turns.

I strongly advise you against watching the trailer or reading anything that may give the plot away, because chances are you will damage the intended abruptness, which for me was one of the most important and enjoyable aspects.