I am no alarmist, nor am I affected with spy mania. I am merely here writing a plain and bitter truth, the truth which I have learnt after years of experience and patient inquiry. If space permitted, I could relate a hundred stories of espionage, all supported by evidence; stories which would contain as much excitement as any I have ever written in the guise of fiction. But my only object in this preface is to urge the public to read this book, to inquire into and study the problem for themselves, and to assure them that the words of "Ex-Intelligence Officer" are full of very grave truths, which cannot be ignored or refuted. It is for the public themselves to demand satisfaction in a very determined and outstanding manner. The voice of the country is unanimous that we are being trifled with, and surely it is a thousand pities that mistrust should thus arise, as it is rapidly arising, at this grave crisis of our national history. The public have been told definitely by Mr Tennant that "Every enemy alien is known, and is now under constant police surveillance." If the public, in face of the mass of evidence accumulating to the contrary, will still believe it, then let them rest in their fool's paradise until the Day of Awakening. If not, then they, through their representatives in Parliament, have the matter in their own hands. ------------------------------------------------------------------------ William Le Queux. Devonshire Club, London S.W. April 1915. Foreword. British and other official circles know more of the German secret service than the public are aware of, and there is little that is done by German agents without the cognisance of the countries affected by their work, at the present time. The following pages make no attempt at unveiling all the secrets of the German system, for that would involve not a book, but a library. What has been done is to present such evidence with regard to the system as can be verified from unquestionable sources--the book given here in no case goes beyond the truth, and is capable of proof, with the exception of the chapter on _agents provocateurs_, of whose work no direct proofs are available to the general public. In this case the writer has been careful to state facts in such a way that they carry their own proof.