"We must follow," I said, and raising my long sword I struck the panel a heavy blow that would have shattered much thicker planking, but I only made a scratch upon it, tearing away a little piece scarce thicker than a fingernail, but the scar that I had made revealed the harrowing truth--the panel was constructed of forandus, the hardest and the lightest metal known to Barsoomians. I turned away. "It is useless," I said, "to attempt to pierce forandus with cold steel." Tavia had crossed to us and was standing in silence, looking up into my face. Her eyes were bathed with unshed tears and I saw her lips tremble. "Hadron!" she breathed. "You have come back from the dead. Oh, why did you come, for this time they will make no mistake." "You know why I came, Tavia," I told her. "Tell me," she said, very soft and low. "For friendship, Tavia," I replied; "for the best friend that a man ever had." At first she seemed surprised and then an odd little smile curved her lips. "I would rather have the friendship of Hadron of Hastor," she said, "than any other gift the world might give me." It was a nice thing for her to say and I certainly appreciated it, but I did not understand that little smile. However, I had no time then in which to solve riddles; the problem of our safety was the all important question, and then it was that I thought of the vial in my pocket pouch. I looked quickly about the room. In one corner I espied a pile of sleeping silks and furs; something there might answer my purpose; the contents of the vial might yet give us all freedom if I had but time enough. I ran quickly across the room and searched rapidly until I had found three pieces of fabric that were at least better suited to my purpose than any of the others. I opened my pocket pouch to withdraw the vial and at the same instant I heard the pounding of running feet and the clank and clatter of arms. Too late! They were already at the door. I closed my pocket pouch and waited. At first it was in my mind to take them on in combat as they entered, but I put that idea aside as worse than useless, since it could result in nothing but my death, whereas time might conjure an opportunity to use the contents of the vial. The door swung open, fully fifty warriors were revealed in the corridor without. A padwar of the guard entered followed by his men. "Surrender!" he commanded. "I have not drawn," I replied. "Come and take it." "You admit that you are the warrior who attacked the prince, Haj Alt?" he demanded. "I do," I replied. "What have these women to do with it?" "Nothing. I do not know them. I followed Haj Alt here because I thought that it would give me the opportunity that I have long sought to kill him." "Why did you want to kill him?" demanded the padwar. "What grievance have you against the prince?" "None," I replied. "I am a professional assassin and I was hired by others." "Who are they?" he demanded.