The Yellow Dove - George Gibbs

A World War 1 spy vs spy novel. Oh! And perhaps I should also mention, a bit of romance?
"I am sorry,” he said coolly, "awfully sorry. As you know, I would have had things different. You may still doubt me when I say that what I have done is the hardest task that I ever undertook in my life. But that is true. You were the only person in England who jeopardized my existence there. I had to take you away. I regret the necessity of having to use force. I shall do what I can here upon the Sylph to counteract the unpleasant impression of my brutality. I am not a bully and a woman-baiter. I am a spoke in the wheel of destiny which you had clogged. By all the rules of the game you should have died. Reasons which I need not mention made your death at my hands an impossibility. So I merely removed you to a place of safety. No harm shall come to you, I pledge my honor." (Excerpt from Chapter 13.)