E. Phillips Oppenheim 
The Great Secret [EPUB ebook] 

Mr. Hardross Courage is a wealthy young Englishman whose life has been carefree and uneventful. He plays cricket for his county, he attends to the management of his estates, he serves as a local magistrate. He has never taken any interest in a career of any sort. On a trip to London to participate in a cricket match, Hardross is confronted by a man who forces his way into his hotel room imploring him to hide him. His reason, “They want to kill me.” So begins a tale that is likely to change Hardross’ idyllic life forever to one of mystery and espionage.
The Great Secret is an entertaining tale of adventure. If you have a fondness for early 20th century spy fiction you should find this to be an entertaining read.