She said this in a low voice, as she inspected Nick Carter’s countenance in a way that might have been embarrassing to a less self-possessed person. To him it was only amusing. “What I can’t understand,” she continued, “is how you come to be in this box, number thirty-six, and why you are in the costume that the other gentleman ordered this afternoon. I know he asked for a Mexican dress, and that the clerk showed him this one--or one like it, for I was with him at the store.” “I believe I can explain part of the mystery,” returned Nick. “As a matter of fact, this is not my costume. I ordered an entirely different one from Corliston’s----” “Corliston!” repeated the girl. “Yes, that was the firm we went to.” “The usher who put me into this box judged me by my dress, I suppose,” smiled Nick. “He had been told to put a Mexican into thirty-six, and he did as he had been instructed. So we can’t blame the man.” Nick Carter could see that the cheeks of the girl were gradually losing their pallor, as if she had been relieved of some great anxiety. “Are you sure this coffee is drugged?” he asked. “There is no doubt about that,” she answered quickly. “There are two men below who have mistaken you for the--for the other gentleman, and they are going to do him injury if they can.” “Why?” “That I can’t tell you. But the men are very dangerous. Moreover, if they find out that I have come here to warn you, they will kill me.” “I hardly think that,” answered Nick Carter. “This is New York. It is not safe to kill people here. Still, some men will take chances. Especially foreigners, and the names you have mentioned have that sort of sound. Did you say Solado and Miguel were watching this box?” “Yes.” “Very well. If you will permit me to walk with you, we’ll make a tour of the ballroom and see what we can find out. I give you my word they shan’t kill you while I am with you,” he added, with one of those confident smiles which had given courage to so many persons with whom he had had dealings in the past. She hesitated, but the detective knew she would do as he had suggested. CHAPTER II. WHAT NICK FOUND IN HIS SLEEVE. “Do you realize that, if Solado and Miguel believe you to be Prince Marcos, your own life may be in danger--even in this ballroom?” asked the girl. “I don’t think it will.” “Why should you trouble yourself about something in which you have no interest?” she persisted. “Who says I have no interest in it?” was his rejoinder. “Since I find myself in this affair, I should like to see it through. You do not know me, but I assure you it will give me pleasure to help you, if I can. There is one thing I can tell you, and that is that Prince Marcos is probably in the uniform of a Spanish colonel. That was what I ordered, and if I have his dress, most likely he has mine. Corliston’s have mixed it up, that’s all.” “It seems likely,” she murmured. “More than likely. Will you come?”