Taking the key, Malcolm Sage kneeled before the safe door and, by the light of an electric torch, surveyed the whole of the surface with keen-sighted eyes. Then placing the key in the lock he turned it, and swung back the door, revealing a long official envelope as the sole contents. This he examined carefully without touching it, his head thrust inside the safe. "Is this the same envelope as that in which the document was enclosed?" he enquired, without looking round. The three men had risen and were grouped behind Malcolm Sage, watching him with keen interest. "It's the same kind of envelope, but----" began Sir Lyster, when Lord Beamdale interrupted. "It's the envelope itself," he said. "I noticed that the right-hand top corner was bent in rather a peculiar manner." Malcolm Sage rose and, taking out the envelope, carefully examined the damaged corner, which was bent and slightly torn. "Yes, it's the same," cried Mr. Llewellyn John. "I remember tearing it myself when putting in the document." "How many leaves of paper were there?" enquired Malcolm Sage. "Eight, I think," replied Sir Lyster. "Nine," corrected Lord Beamdale. "There was a leaf in front blank but for the words, 'Plans Department.'" "Have you another document from the same Department?" enquired Malcolm Sage of Sir Lyster. "Several." "I should like to see one." Sir Lyster left the room, and Malcolm Sage removed the contents of the envelope. Carefully counting nine leaves of blank white foolscap, he bent down over the paper, with his face almost touching it. When Sir Lyster re-entered with another document in his hand Malcolm Sage took it from him and proceeded to subject it to an equally close scrutiny, holding up to the light each sheet in succession. "I suppose, Sir Lyster, you don't by any chance use scent?" enquired Malcolm Sage without looking up. "Mr. Sage!" Sir Lyster was on his dignity. "I see you don't," was Malcolm Sage's calm comment as he resumed his examination of the dummy document. Replacing it in the envelope, he returned it to the safe, closed the door, locked it, and put the key in his pocket. "Well! what do you make of it?" cried Mr. Llewellyn John eagerly. "We shall have to take the Postmaster-general into our confidence." "Woldington!" cried Mr. Llewellyn John in astonishment. "Why." Sir Lyster looked surprised, whilst Lord Beamdale appeared almost interested. "Because we shall probably require his help." "How?" enquired Sir Lyster. "Well, it's rather dangerous to tamper with His Majesty's mails without the connivance of St. Martins-le-Grand," was the dry retort. "But----" began Mr. Llewellyn John, when suddenly he stopped short. Malcolm Sage had walked over to where his overcoat lay, and was deliberately getting into it. "You're not going, Mr. Sage?" Sir Lyster's granite-like control seemed momentarily to forsake him. "What do you advise us to do?" "Get some sleep," was the quiet reply.