The book follows the life of Fritz, from growing up in the Boer War, to his Old age in the USA. Fritz was an idealistic man who witness horrors in his childhood that shaped him to become one of the biggest Spies for the Nazis in WWII. His hatred for the British Empire drove him towards always seeking revenge upon them that eventually he spends the majority of his later life behind bars.
I encourage anyone who wishes to read this cautionary tale to do so with an open mind. One should not condone what Fritz did, bit learn from it. I also would recommend anyone who wants to write good antagonists or villains in fiction to study Fritz. His life is an example of a man who's genuine desire for Justice (but misguided moral compass) lead him to join ranks with the Third Reich.