There was no door leading to the roadway save the great entrance gate. Through that Miller and his companions had certainly not passed, therefore I concluded that they had reached the house by a secret way through the vineyard. Careful to remain always in the shadow, and moving with greatest caution, I retraced my steps, entered the vineyard at the point where I had seen one figure disappear, and after a few moments discovered a narrow path through the trailing richly laden vines which led through an open gate to a small side door in a wing of the great old building. I tried it. The handle yielded. They had passed through there, without a doubt! Should I enter there? Was I not perhaps risking my life in so doing? They were a desperate trio. I knew well my fate, if they discovered that I had learned their secret. I held my breath. Then with sudden resolve, I slowly pushed the door open and peered eagerly within. Next instant I drew back aghast. What I saw there staggered me. I was not prepared for it. I could distinctly hear my own heart beating within me. CHAPTER THIRTY ONE. THE SECRET OF THE VILLA VERDE. The unexpected sight that met my eyes within that narrow stone passage was truly horrifying. An oil lamp shed a faint light at the farther end of the narrow tunnel-like place, and revealed the body of a man lying in a heap in such a position that I saw, in an instant, that some tragedy had occurred. Creeping forward I bent beside him and touched his hand. It was still warm, yet I saw across the stones a large dark pool--a pool of blood, and at the same moment discovered that it issued from an ugly knife-wound just over the heart. He was a respectably dressed man of forty, robust, heavily built, with dark moustache and shaven chin. As I touched his hand, which lay helpless at his side, my fingers came into contact with something hard, and I found that strapped around his waist he carried a revolver. Quickly I took it out, for I had no weapon myself, and at a glance saw that it was the regulation pattern as supplied to the agents of police. The man who had been stabbed to the heart so unerringly was probably a detective who had been left in charge of the villa after the police had taken possession of the place. Hearing a summons at the door he had perhaps gone to open it, when the ready knife had struck him down, and the desperate trio had passed over his body and entered the villa to prosecute their mysterious object. I listened. There was no sound. The intruders, whatever their object, were in the main building; for it seemed that this narrow passage merely gave entrance to the servants' quarters. The place was an enormous, rambling one, built, as I afterwards found, by Prince Torlonia in the days of the Borgia Pope, once full of splendour and magnificence, but sadly neglected and degenerated in these modern days.