Sax Rohmer

“ You will mount guard during my absence. If anyone comes up—anyone, mind—it will be your job to invent some story to account for your presence and to induce the inquirer to return, without giving him, or her, an opportunity of seeing this ladder and the open trap. Do you understand?”
“Quite,” said Latham, entering into the spirit of the thing. “Count upon me absolutely.”
“Good!”
Harley nodded, mounted the ladder, and without very much difficulty, raised the wooden trap. ”

“ Harley turned, looking into the other's face.
“I may need you, Latham, I admit,” he replied, “but unfortunately I cannot avail myself of your offer, much as I should like to. It is imperative that I should be alone in the library, tonight. Otherwise, the murder machine will not be set in motion and all my efforts will have been wasted.”
“I don't understand,” muttered Latham, “but I am beginning to realize that some awful peril overhangs this house. It seems to center in the library; and the idea of your submitting yourself to it, alone, is not a nice one to contemplate.” ”

“ Then the light of the electric torch shone out from the depths of the chair, touching the framed photograph in the recess of the overmantel. A moment it glittered there. To the accompaniment of a faint click the ray disappeared. Utter darkness fell. ”