“Do, please. It will be time enough to consider Zenobia’s part in the mystery when we have heard from the theatrical costumiers. One moment----” Captain Charles had taken a step towards the exit--“I should like you to wait till I have put a question to Madame Bonnell.” He touched the nearest bell-push as he spoke, and the Inspector and I looked at each other with curiosity as to his purpose. The bell was promptly answered by Gerard, and within a few moments the proprietress of the club sailed into the room. She was decidedly more at ease than she had been when we interviewed her first. Touches of mourning had been added to her elegant dress, and her whole manner had been toned down to that of a dignified lady in distress. Tarleton appeared to meet this assumption by an added roughness in addressing her. “Will you be good enough to tell me the rules of the Domino Club as to the admission of visitors?” Madame Bonnell put her head on one side for a moment, giving herself the air of a person who was considering whether to grant a favour. “I see no objection to that, Sir Frank. You are Sir Frank Tarleton, are you not?” The question was almost impudent. The physician ignored it with a sharp “Well?” “Every member was entitled to one card of admission for a friend for each dance. He was required to enter the name of the friend, and the costume he was coming in, in the club register.” “Let me see the register, please.” Madame had evidently expected this demand. She drew herself up. “The register is confidential. It contains the names of all the members. I keep it for my private information, and I can’t show it to anyone else.” Tarleton turned to the Police Inspector with a shrug. “I must ask you to do your duty, after all, I’m afraid.” The Frenchwoman turned red with excitement. “But what does this mean? Have you seen the papers?” She produced an evening paper from her dress, one of those evening papers that come out early in the forenoon. “Here it is announced that His Royal Highness the Crown Prince of Slavonia honoured me by his presence here last night. My club is under royal patronage, you see, gentlemen. This is not an affair for the police.” My chief had described Captain Charles as thorough. He showed his quality as soon as the angry woman had spoken. First setting a whistle to his lips, he stepped forward and placed a firm hand on her arm. “I arrest you in the King’s name.” CHAPTER VI THE BOOKS OF THE DOMINO CLUB It was at once evident that Sir Frank Tarleton had taken the measure of his opponent accurately. As soon as she felt the police officer’s touch Madame Bonnell’s confidence deserted her, and she collapsed in a state of mingled panic and bewilderment. “_Mon Dieu!_ But what have I done? What is it that I am accused of?” She looked imploringly from Charles to Tarleton and from him to me. It was the Inspector who answered.