This groundwork carefully prepared, I had comparatively little fear of the results of actual discovery when I set to work upon the warrior of Phundahl and the assassin of Toonol. I chose the former first. His lung was badly injured where my blade had passed through it, but from the laboratory where were kept fractional bodies I brought a perfect lung, with which I replaced the one that I had ruined. The work occupied but half the night. So anxious was I to complete my task that I immediately opened up the breast of Gor Hajus, for whom I had selected an unusually strong and powerful heart, and by working rapidly I succeeded in completing the transference before dawn. Having known the nature of the wounds that had dispatched these two men, I had spent weeks in performing similar operations that I might perfect myself especially in this work; and having encountered no unusual pathological conditions in either subject, the work had progressed smoothly and with great rapidity. I had completed what I had feared would be the most difficult part of my task and now, having removed as far as possible all signs of the operation except the therapeutic tape which closed the incisions, I returned to my quarters for a few minutes of much needed rest, praying that Ras Thavas would not by any chance examine either of the subjects upon which I had been working; although I had fortified myself against such a contingency by entering full details of the operation upon the history card of each subject that, in the event of discovery, any suspicion of ulterior motives upon my part might be allayed by my play of open frankness. I arose at the usual time and went at once to Ras Thavas’ apartment, where I was met with a bombshell that nearly wrecked my composure. He eyed me closely for a long minute before he spoke. “You worked late last night, Vad Varo,” he said. “I often do,” I replied, lightly; but my heart was heavy as a stone. “And what might it have been that so occupied your interest?” he inquired. I felt as a mouse with which the cat is playing. “I have been doing quite a little lung and heart transference of late,” I replied, “and I became so engrossed with my work that I did not note the passage of time.” “I have known that you worked late at night. Do you think it wise?” At that moment I felt that it had been very unwise, yet I assured him to the contrary.