Der Mörder

Hans Kuperus lives in an orderly environment with his wife and a maid in a small Dutch town. Every month, he attends a doctors' meeting, only skipping it twice. The first time, to confirm that his wife is indeed cheating on him, as an anonymous letter claims. The second time, he shoots the two people, whose bodies he then throws into the canal. No one suspects him, and his life continues as usual. But then Kuperus discovers who the sender of the letter was. And as the ice melts, the canal reveals the two bodies.