“Yes. I must tell Marcos that Solado is here. But you must not go in that costume.” Nick Carter had already readjusted the black mask over his face, but the girl could tell, from the set of the firm chin, that this man, a stranger to her, was determined to have his way. “I have never yet seen the man of whom I was afraid,” he returned. “There will be no danger, I assure you.” She could not resist his masterful manner. He held out his hand. She took it, and he led her out of the box. They walked along the corridor, the girl leaning on his arm, and so down the staircase to the ballroom. As they entered, a dance was just over, and the dancers, chatting and laughing, were leaving the floor. “All the better,” he whispered, behind his mask. “We shall have plenty of room to walk, and a good opportunity to look at everybody as we go along.” Nick Carter, a gallant figure in his gay Mexican dress, and with the sombrero pulled well down over his forehead, strode around the ballroom, the “Queen of Night” by his side. They had almost entirely encircled the great hall without seeing anything of a Spanish officer, either on the floor, in the balcony, or in any of the boxes. “It seems as if he isn’t here,” remarked Nick to his companion. She did not answer, but her fingers suddenly tightened on his arm. “Don’t look into that alcove on the right,” she whispered. “Solado and the other man I mentioned are in there, watching us.” They walked on a few paces. Then Nick Carter, in a natural manner, looked around him, as if taking a general view of the scene. He saw two men, in the rich garb of Indian princes, with jewels blazing all over them, moving away from the alcove in the direction of the wide doorway at the other end of the ballroom. It was the only way by which any one could enter or leave. There were several emergency fire exits, but all were fastened shut. They would open automatically in case of need, but were not used otherwise. This was an invitation affair, and the famous society leader, Mr. van Raikes, was the hostess. “You see?” she murmured. “Do be careful, sir. They are desperate and dangerous men.” “Desperate and dangerous men are the kind one often has to meet in this world,” he replied lightly. “What do you suppose they are going to do now?” “They will try to prevent your getting away,” was her response. “I feel sure of that. They have seen me with you, and they will know I have told you about them. Of course, they think you are Prince Marcos.” “That means that you are in danger,” returned Nick, rather more thoughtfully than he had spoken heretofore. “We shall have to----” “It makes no difference about me,” she answered, drawing a quick breath. “I beg your pardon. It matters a great deal. I don’t know what this is all about, nor who Prince Marcos and these other men are. But it looks as if there is something that puts you in an awkward situation. Therefore, I must ask you to depend on me.”