The desk in question was a big important-looking writing table of mahogany set across a corner by the window. Lord Mayfield went over to it, and began sorting through the various documents laid out.

“Lovely night now,” said Sir George.

Mr. Carlile agreed.

“Yes, indeed. Remarkable the way it’s cleared up after the rain.”

Putting away his file, Mr. Carlile asked:

“Will you want me any more tonight, Lord Mayfield?”

“No, I don’t think so, Carlile. I’ll put all these away myself. We shall probably be late. You’d better turn in.”

“Thank you. Goodnight, Lord Mayfield. Goodnight, Sir George.”

“Goodnight, Carlile.”

As the secretary was about to leave the room, Lord Mayfield said sharply:

“Just a minute, Carlile. You’ve forgotten the most important of the lot.”

“I beg your pardon, Lord Mayfield.”

“The actual plans of the bomber, man.”

The secretary stared.

“They’re right on the top, sir.”

“They’re nothing of the sort.”

“But I’ve just put them there.”

“Look for yourself, man.”

With a bewildered expression, the young man came forward and joined Lord Mayfield at the desk.

Somewhat impatiently the Minister indicated the pile of papers. Carlile sorted through them, his expression of bewilderment growing.

“You see, they’re not there.”

The secretary stammered:

“But—but it’s incredible. I laid them there not three minutes ago.”

Lord Mayfield said good-humouredly:

“You must have made a mistake, they must be still in the safe.”

“I don’t see how—I know I put them there!”

Lord Mayfield brushed past him to the open safe. Sir George joined them. A very few minutes sufficed to show that the plans of the bomber were not there.

Dazed and unbelieving, the three men returned to the desk and once more turned over the papers.

“My God!” said Mayfield. “They’re gone!”

Mr. Carlile cried:

“But it’s impossible!”

“Who’s been in this room?” snapped out the Minister.

“No one. No one at all.”

“Look here, Carlile, those plans haven’t vanished into thin air. Someone has taken them. Has Mrs. Vanderlyn been in here?”

“Mrs. Vanderlyn? Oh, no, sir.”

“I’ll back that,” said Carrington. He sniffed the air! “You’d soon smell if she had. That scent of hers.”

“Nobody has been in here,” insisted Carlile. “I can’t understand it.”

“Look here, Carlile,” said Lord Mayfield. “Pull yourself together. We’ve got to get to the bottom of this. You’re absolutely sure the plans were in the safe?”

“Absolutely.”

“You actually saw them? You didn’t just assume they were among the others?”

“No, no, Lord Mayfield. I saw them. I put them on top of the others on the desk.”

“And since then, you say, nobody has been in the room. Have you been out of the room?”

“No—at least—yes.”

“Ah!” cried Sir George. “Now we’re getting at it!”

Lord Mayfield said sharply:

“What on earth—” when Carlile interrupted.