It was a great house. The flower of Russia's nobility was gathered in the boxes and stalls of the vast building, the men attired in immaculate costume, the women radiant in their flashing jewels. In a far box, Nello saw the charming young Princess with an elderly friend, acting as her chaperon in place of her mother. Evidently she had not taken his advice. He cast a lightning glance around as he bowed to the plaudits of the audience. He was looking for Zouroff, but he could not see him. If the Prince was in the crowded house, he had missed him. Certainly he was not in the box where his sister sat. He conducted the overture. In a few moments the curtain would rise. Before he had got to the end of the last few bars, there was heard a piercing scream, the cry of a woman. It penetrated to every corner of the building and created an uneasy feeling in the audience. Nello recognised the situation at once. He beat with his bâton on the desk and started the overture again. Something had happened. He would know in a few minutes. At last the curtain rose. The stage-manager, looking very agitated, appeared. In a few brief sentences he explained that Madame Quéro had been attacked with sudden indisposition; that he must crave the indulgence of the audience for her understudy, who would take her place. Corsini dared not leave his desk. On such a night as this he could not affront his Emperor and this brilliant assemblage by deputing his task to a subordinate. He went through the Opera with the conscientious spirit of the artist. But all the time his thoughts were dwelling on La Belle Quéro, the woman who had braved Zouroff's vengeance in order to save him. It was evidently a serious indisposition. If it had been only a slight attack, the handsome singer would have pulled herself together and appeared some time in the course of the evening. With her jealous temperament, she was not the woman to give an understudy too big a chance. At last the Opera was over, the brilliant crowd filed out. Corsini went round to the wings to inquire after La Belle Quéro. One of his subordinates gave him the information he sought. "Madame Quéro is very ill, Signor. The doctor was called in. He did not seem quite able to diagnose her symptoms. He had her conveyed home and consigned to the care of her own maid and her own physician." Corsini at once despatched a messenger to the villa, with instructions to report to him at his hotel. The man came back with disquieting news. The singer was still in a comatose state, and her life was despaired of. A swift thought swept through the Italian's mind. Had Zouroff anything to do with this, apparently, fatal illness? Had he discovered the part she had played in his rescue?