Jack whispered to Claire to remain where she was a moment, and slipped out of the house into the garden unperceived. It had suddenly occurred to him that perhaps the window leading from the study to the garden was unfastened. He recollected that this was the means by which Anstruther left and returned to the house. It would have been imprudent on the latter's part to use the front door, and there was not much risk in leaving the study window unlatched.

It was just as Jack had expected. The long French window gave to his touch, and a moment later he was in the room. As it happened on the previous occasion, he could see not the faintest trace of any mechanism by means of which the melody was conveyed from the Great Metropolitan Hotel to Panton Square. And yet the whole room was flooded with it; rising and falling in triumphant strains, as if mocking the intellect of a man who had brought this wonderful result about. But there was no time to speculate on that, no time for close investigation. On the other side of the door the voices of Anstruther and Bates were rising to a still more angry pitch, and Claire's tones of expostulation came to Jack's ears. As he crossed the room he could see that the key was in the door. He flung it open, and Anstruther came staggering backward into the room, closely followed by the detective.

"You can see that the game is up," the latter said coolly. "Why not make a clean breast of it? I shall find out how this is done, if I have to pull down the house to do it."

Anstruther smiled in a scornful kind of way, and flung himself doggedly into a seat. He bade Bates do his worst, and prophesied that the police would suffer for this indignity. But Bates was not listening. He was pacing rapidly round the room with his ear to the wall, as if scenting out some clue to the mystery. A moment later, and there came into the room the form of Serena.

One glance at her sufficed to show that she was not the Serena whom Jack had known so long. The demure, downcast eyes were no longer seeking the floor as of old; there was no shrinking and timidity on the part of the woman now. She was changed almost beyond recognition. She walked with a firm, elastic tread, her shoulders were thrown back, and her head uplifted fearlessly. From under his heavy brows Anstruther glanced at her suspiciously.

"Go away," he commanded hoarsely. "How dare you force yourself in here like this! Go, woman."

But the tones of command had evidently lost their power. There was no shrinking on Serena's part. She advanced into the middle of the room as if the place belonged to her.

"No, no," she cried in tones as clear and ringing as Anstruther's own. "Your power has gone forever. For three long patient years I have waited for this moment. God only knows what my life has been, and what a hell your cruelty has created for me. But the cord is broken now. Only to-night I have learned the truth. I have been your good and faithful servant; I have stooped to do your hateful work; I have been the ally of criminals--of your creature Redgrave, amongst others; and all because I thought you held my life in the hollow of your hand."

"Tell them the story of your boy," Anstruther sneered.

"I will tell them the truth," Serena cried. "You said you could hang me if you liked. You pretended that in my delirium I had taken the life of my darling child. You were shielding a murderess, as I thought. But it was a black and cruel lie. Give me back my wasted years, you coward; give me back my sleepless nights and dreary days. But, thank God, that time has passed. My boy is alive--alive! He is safe in the house at present!"