"Never mind my dress," he said shortly. "You can lend me your frock, and if you have no further business here, you can do me a service." As they went out together, Robin explained to his friend the manner in which he had obtained a domino and an invitation, and, incidentally, the predicament of Lord Beachcombe. Together they sought and found his carriage, at a place previously arranged for, and within it the exchange of garments was effected. "Now go to the house by the riverside, where you will find Lord Beachcombe tied hand and foot in the dark in the guard-room, and his lackeys under similar conditions in another room. Steve Larkyn is in charge of them. Restore the mask and domino to Lord Beachcombe, return him and his varlets to the carriage, blindfolded, and when you have taken them a safe distance from Essex Street, set them free to go their way to the ball or the devil, whichever pleases them." The carriage drove away and Robin, completely concealed under the monk’s gown, made his way back to the house. Not, however, through the brilliantly lighted main-entrance, but this time by a side-door that led to the servants’ quarters. *CHAPTER XVI* *AT THE UNMASKING* When Prue and Robin had left the conservatory a sufficiently long time to insure their return to the ball-room, out from behind a clump of plants slipped Sir Geoffrey Beaudesert. Observing her exit from the ball-room with a tall and conspicuously habited masker, he had followed with the intention of interrupting a tête-à-tête and forestalling one of Prue’s little flirtations that, however harmless in themselves, were dangerous, as he knew by experience, to anterior claims. When he found that, avoiding the well-lighted rooms, Prue guided her companion to an out-of-the-way retreat, where it was unlikely that they would be disturbed by any one less familiar with the house than herself, his annoyance increased, and with it his anxiety to know who the favored swain might be, and when Peggie, with the good-natured intention of giving Robin an opportunity, left them to rid herself of her sheepskin, the green-eyed monster took complete possession of Sir Geoffrey and prompted a baseness of which, a moment before, he would have blushed to think himself capable. The only available concealment was at such a distance that at first nothing reached him but the murmur of voices. He could see that Prue stretched out her hands to her companion, and that he kissed them with ardor, but until his own name was mentioned, he heard nothing but a disjointed word here and there. Then, with ears preternaturally sharpened by something even more poignant than jealousy, he overheard Prue’s repudiation of himself and her companion’s expression of relief and gratitude for the same.