When Richard and Isaac Thornycroft left the dining-room, so unobtrusively as not to draw attention to the fact, they passed through the small door at the further end of the hall. Isaac, the last, silently locked it, thereby cutting off all communication with the busy part of the house. Swiftly ascending to Richard's chamber, they changed their clothes for others which were laid out in readiness. Hyde, his clothes also changed, was in waiting at the foot of the stairs when they came down, and he crossed with Isaac to the coach-house opposite, built, as must be remembered, on a portion of the old ruins. Richard undid the door in the wall looking to the front, and stayed there until joined by the breathless Tomlett--as above seen. The dog-cart was in its place in the coach-house; the broken old cart and the bundles of straw were in the corner; all just as usual. Tomlett and Hyde removed the cart and the straw from their resting place (whence, by all appearance, they never were removed), and the brothers Thornycroft lifted a trap-door, invisible to the casual observer, that the straw had served to conceal. A flight of steps stood disclosed to view, which Isaac and Richard descended. The steps led to a subterranean passage; a long, long passage running straight under the plateau and terminating in a vault or cavern, its damp sides glistening as the light of the lantern flashed upon it. Traversing this passage to the end, Isaac put the lantern down: then they unwound a chain from its pulley, and a square portion of the rock, loose from the rest, was _pulled in_ and turned aside by means of a pivot: thus affording an ingress for goods, smuggled or otherwise, to come in. No wonder Robert Hunter had thought the rock sounded hollow just there! Ah, Mr. Kyne had scented the fox pretty keenly. But not the huntsmen who rode him to earth. It took longer to do all this than it has to relate it. When Richard had helped Isaac to remove the rock, he returned along the passage on his way to the plateau. It was customary for one of the two brothers to stand on the plateau on the watch during these dangerous feats, with his descending signal of warning in case of alarm. Richard took that post to-night. Oh, that it had been Isaac! But it was marvellous how lucky they had hitherto been. Years had gone on, and years, and never a check had come. One great reason for this was that the late supervisor, Mr. Dangerfield--let us only whisper it!--had allowed himself to be bribed. What with that, and what with the horror the preventive men had of the plateau, the daring and profitable game had been carried on with impunity. Richard Thornycroft went on his way, little knowing the awful phantom that was pursuing him.