The Infiltrator is an American film about an Israeli freelance journalist who travels to Germany c. the early 1990s and uncovers a dangerously pervasive underground Neo-Nazi faction with the intent to bring Nazism back to the forefront in Germany. It is based on the book "In Hitler's Shadow: An Israeli's Journey Inside Germany's Neo-Nazi Movement" by Yaron Svoray and Nick Taylor
The Infiltrator and In Hitler's Shadow: An Israeli's Journey Inside Germany's Neo-Nazi Movement are both similar but not exactly the same.
The Infiltrator is based on the book Hitler's Shadow. Movies based on books have similar plots but are not always exactly the same down to the finest detail.