"Somebody's room was empty. Across the corridor, the door of the oak room was partly open. A candle had been indiscreetly left there, lighted, on the edge of the mantel—"
"My father put that candle there," said Hugh, "when he explored—"
"It had been lighted," said Dr. Fell, "against Somebody's return. When I saw the piece of panelling open—"
There was something odd in the doctor's manner; something labored; he went on talking as though he were giving a long explanation for the benefit of some person unseen, and using Hugh only as an audience.
"Why," said the latter, "are you telling me this?"
"Because the murderer did not return," replied Dr. Fell. He had raised his voice, and it echoed in the narrow hall. "Because I stood at the entrance to the secret passage on the outside, and waited there until Murch came up over the hill to tell me the news. The murderer could not get back. The murderer was locked out of that house, with all the downstairs windows locked, and every door bolted; shut out tonight as certainly as Depping was shut out here just twenty-four hours ago." "Then-"
"The whole house is aroused now. It will only be a matter of minutes before the one room is discovered to be empty. Murch knows it already, and so do — several others. A searching party, with flash lights and lanterns, has begun to comb the grounds. The murderer is either hiding somewhere in the grounds, or" — his voice lifted eerily—"is here."
He took his hand off the newel post and stood upright.
"Shall we go upstairs?" he asked gruffly.
After a pause Hugh said quietly, "Right you are, sir. But I suppose Murch told you the fellow's a dead shot, and he's still armed?"