A surprise awaited them from the first. True, the hall was in darkness, and, as far as they could judge, so was the rest of the house. But from somewhere upstairs came the unmistakable sound of a piano, and of somebody singing in a sweet but plaintive soprano voice. Gurdon clutched his companion by the arm. "Don't you think it is just possible that we have made a mistake?" he whispered. "Isn't it quite on the cards that this is a genuine affair, and that we are intruding in an unwarrantable manner upon some respectable private citizen? I am bound to say that that beautiful voice does not suggest crime to me." "We must go on now," Venner said, impatiently. "It won't do to judge by appearances. Let us go up the stairs and see what is going on for ourselves. If we are intruding, we will get away as speedily as possible." Gurdon made no further objection, and together they crept up the stairs. There was no chance of their being surprised from behind by the servants, for they had taken good care to notice that the basement was all in darkness. They were getting nearer and nearer now to the sound of the music, which appeared to come from the drawing-room, the door of which was widely enough open for the brilliant light inside to illuminate the staircase. A moment later the music ceased, and someone was heard to applaud in a hoarse voice. "Sing some more," the voice said. "Now don't be foolish, don't begin to cry again. Confound the girl, she makes me miserable." "Do you recognise the voice?" Venner whispered. "Lord! yes," was Gurdon's reply. "Why, it's Fenwick. No mistaking those tones anywhere. Now, what on earth does all this mean?" "We shall find out presently," Venner said. "You may laugh at me, but I quite expected something of this kind, which was one of the reasons why I obtained the keys of the house." "It's a most extraordinary thing," Gurdon replied. "Now isn't this man--Fenwick--one of the last persons in the world you would credit with a love of music?" "I don't know," Venner said. "You never can tell. But don't let's talk. We are here more to listen than anything else. I wish we could get a glimpse of the singer." "I am going to," Gurdon declared. "Unless I am greatly mistaken, I have made a discovery, too. Oh, I am not going to take any risk. Do you see that mirror opposite the door? It strikes me if I get close enough to look into it that I shall be able to see who is in the room without betraying my presence." So saying, Gurdon crept forward till he was close enough to the mirror to get a very good idea of the room and its occupants. He could see a pale figure in white standing by a piano; he could see that Fenwick was sprawling in a big armchair, smoking a large cigar. Then he noticed that the girl crossed the floor and laid a slim hand half timidly, half imploringly, on Fenwick's shoulder.