Fatherland is a crime novel taking place in the mid 1960's Berlin. Hitler is still alive and won the war.
The plot follows police detective Xavier March, and his investigation of the death of a high-ranking Nazi. Soon March realizes that he is in the middle of a political scandal in which senior party leaders kill a certain group of people. He's supposed to be taken off the case.
However, March meets an American journalist, Charlie Maguire, who knows the case from a different angle.
After both travel to Zurich together to check out the bank account of one of the victims, they uncover the missing details behind the murders.
Now though the plot may sound kind of interesting (which it really is!), it's the whole set up of the novel that gets the reader. Harris creates a Germany, a Berlin and a completely new history without going nuts on the amount of creative possibilities, but with a lot of research and sense. It's even more awesome if know Berlin and which areas of the town he's actually talking about.
The novel really does create an impression of Nazi Germany if Hitler had won the war. It also shows how European countries and in fact the rest of the world deal with it (or not). It shows how people live and fear, and you're never 100% sure if they follow their leader because they want him or because they have to. It also creates a new level to the question of knowing.
And because the whole novel is so amazing, the end is almost too good to be true.