“You’ve taken my breath away,” Granet declared.  “Let me realise this for a moment.”

He sat quite still.  A rush of thoughts had crowded into his brain.  First and foremost was the thought of Geraldine.  If he could cover up his traces!  If it were true that he was set free now from his pledges!  Then he remembered his visitor of the evening and his heart sank.

“Look here,” he confessed, “in a way this is a huge relief.  I, like you, thought it was to last for three months and I thought I could stick it.  While the excitement of the thing was about it was easy enough, but listen, uncle.  That Norfolk affair—­I am not really out of that.”

“What do you mean?” Sir Alfred demanded anxiously.  “This fellow Thomson?”

“Thomson, of course,” Granet assented, “but the real trouble has come to me in a different way.  I told you that the girl got me out of it.  She couldn’t stand the second cross-examination.  She was driven into a corner, and finally, to clear herself, said that we were engaged to be married.  She has come up to London, came to me to-night.  She expects me to marry her.”

“How much does she know?” Sir Alfred asked.

“Everything,” Granet groaned.  “It was she who had told me of the waterway across the marshes.  She saw me there with Collins, just before the flare was lit.  She knew that I lied to them when they found me.”

Sir Alfred sighed.

“It’s a big price, Ronnie,” he said, “but you’ll have to pay it.  The sooner you marry the girl and close her mouth, the better.”

“If it hadn’t been for that damned fellow Thomson,” Granet muttered, “there would never have been a suspicion.”

“If it hadn’t been for the same very enterprising gentleman,” Sir Alfred observed, “my correspondence would never have been tampered with.”

Granet leaned a little forward.

“Thomson is our one remaining danger,” he said.  “I have had the feeling since first he half recognised me.  We met, you know, in Belgium.  It was just when I was coming out of the German lines.  Somehow or other he must have been on my track ever since.  I took no notice of it.  I thought it was simply because—­because he was engaged to Geraldine Conyers.”

“You are rivals in love, too, eh?” Sir Alfred remarked.

“Geraldine Conyers is the girl I want to marry,” Granet admitted.

“Thomson,” Sir Alfred murmured to himself,—­“Surgeon-Major Hugh Thomson.  He seems to be the only man, Ronnie, from whom we have the least danger to fear.  Personally, I think I am secure.  I do not believe that that single letter will be ever deciphered, and if it is, three-parts of the Cabinet are my friends.  I could ruin the Stock Exchange to-morrow, bring London’s credit, for a time, at any rate, below the credit of Belgrade.”

“All the same, it seems to me,” Granet declared grimly, “that we should both be more comfortable if there were no Surgeon-Major Thomson.”