"Well, certainly young Schwarz was cast perfectly for the role. He was widely travelled, spoke German fluently, and his English was flawless. They were quick to see the advantages. His proposition was accepted. He was given a brief schooling in their spy system, and then, for show, he was ordered out of Germany--under the fictitious name of Siddons. "The rest was easy. We had a very poor spy system at the beginning of the war. There was no such branch of service as we now call G 2. But it was forming, and to them Schwarz made his way, unfolded his plan, and after a careful checking up on his story they decided to take a chance. A spy within a spy! Wheels within wheels! It was a great idea. Do you see it?" His two auditors made no sign other than a staring, amazed look. "G 2 was at first suspicious," Cowan went on, "but he gave them so much information concerning actual conditions in Germany that they could no longer doubt him. They sent him to an aviation training school, telling him to guard his neck at all times and not run any undue risks. "You know the rest--or most of it. He has been invaluable to us, and to-night he will pull his greatest job. And since I have made free to tell you all this, you may be certain it is his last trip across the lines. He reports that the German High Command is getting a bit suspicious, and he dare not trust his luck much further." McGee, who had been listening with intense interest, exhaled audibly as Cowan finished his narration. "Well!" he exclaimed. "I'll never jump to conclusions again. Now I know why that fellow has always acted like he was answerable to no one but himself. And I thought him yellow! And next I thought he was a spy. Well, I was right about that--but the wrong way around. I take my hat off to him! It takes nerve to fill his job." "It does indeed!" Cowan agreed fervently. "Perhaps you recall how I bawled him out for cutting formation over Vitry that day when we were on our way up for our first action? And how I sent him over the lines on a mission to locate von Herzmann's Circus?" McGee nodded. "I certainly do remember it. You sure said plenty!" "Hokum! All hokum!" Cowan said. "Actually, he was going over on a daylight mission of an entirely different nature, and what I said in your presence was merely to mislead you. Unfortunately, you happened to see him running the Archie fire and saw the signals which he had used again and again in crossing over. When you reported to me, we feared the cat was out of the bag. There seemed to be only one way out--to pledge you to secrecy and lead you to believe that we were simply waiting for the proper time to bag him. I knew you would keep your word, and that is another reason why you are here--as a sort of reward. You are the only one who has ever had any such suspicions." Larkin laughed, mirthlessly. "That makes a lot of chuckle-heads out of the rest of us, doesn't it?"