Captain Franz von Rintelen 
Dark Invader 

Men engaged in Intelligence Services during a war divide their particular opponents into two classes. One consists of neutrals who go out of their way to help the enemy for the sake of gain; and for such men we have not much compassion should they fall upon misfortune. They are interfering in great matters with which they are not concerned, in order to make a little money. The other class is made up of men who, abandoning the opportunities of their own careers, go secretly away in the sacred service of their country, play a lone hand, and run the gauntlet of foreign laws. For such we can have nothing but respect while the fight is going on and friendship when it is over.Captain Franz von Rintelen belongs to this latter class. A young naval officer with every likelihood of reaching to high rank, he went abroad in 1915 and only saw his own country again after the lapse of six strenuous and, in part, unhappy years. The history of those years is told in this book. The conversations which he records depend, of course, upon his memory; the main facts we are able to check, and we know them to be exact.The book is written, as one would expect from his record, without the least rancour, and I think I am not trenching upon the province of criticism when I add-with admirable simplicity. It is a record which is more detailed and concerned with endeavours on a vastly wider scale than is usual in such accounts. One cannot, I think, read it without recognising, apart from the magnitude of the things attempted and done, the terrific strain under which he lived; and this gives a moving and human quality to the narrative which sets it a little apart from any other which I have read. Those who are most saturated in spy stories will find much to surprise them in this volume, and they will not be likely to forget the poignant minutes which he spent on the top of an omnibus in London and the way in which those minutes ended.Finally, here is as good an argument against War as a man could find in twenty volumes devoted to that subject alone.