“They could,” he said. “But we want to avoid that if possible. They are the result of immense thought, and no alteration would be as good. Besides, on one or two points change is simply impossible. Still, something could be done, I suppose, if it were absolutely necessary. But you see the difficulty, Hannay. Our enemies are not going to be such fools as to pick Royer’s pocket or any childish game like that. They know that would mean a row and put us on our guard. Their aim is to get the details without any one of us knowing, so that Royer will go back to Paris in the belief that the whole business is still deadly secret. If they can’t do that they fail, for, once we suspect, they know that the whole thing must be altered.”

“Then we must stick by the Frenchman’s side till he is home again,” I said. “If they thought they could get the information in Paris they would try there. It means that they have some deep scheme on foot in London which they reckon is going to win out.”

“Royer dines with my Chief, and then comes to my house where four people will see him⁠—Whittaker from the Admiralty, myself, Sir Arthur Drew, and General Winstanley. The First Lord is ill, and has gone to Sheringham. At my house he will get a certain document from Whittaker, and after that he will be motored to Portsmouth where a destroyer will take him to Havre. His journey is too important for the ordinary boat-train. He will never be left unattended for a moment till he is safe on French soil. The same with Whittaker till he meets Royer. That is the best we can do, and it’s hard to see how there can be any miscarriage. But I don’t mind admitting that I’m horribly nervous. This murder of Karolides will play the deuce in the chancelleries of Europe.”

After breakfast he asked me if I could drive a car. “Well, you’ll be my chauffeur today and wear Hudson’s rig. You’re about his size. You have a hand in this business and we are taking no risks. There are desperate men against us, who will not respect the country retreat of an overworked official.”