The man laughed as he read the terms of the advertisement. His laugh was hollow — scarcely more than a whisper — yet it had a weird sound in that silent room.

The stranger folded the newspaper and walked into the lobby. He entered a telephone booth and called a number.

“Metrolite Hotel?” he asked. His voice was quiet. “Room 874.”

The man spoke again a few moments later.

“Mister Vincent?” he asked. “Sorry I can not go with you tonight. I am detained at home. I have to stay there once in a while. You understand, of course.”

The emphasized words phrased the sentence: “Go at once.”

Twelve minutes later, Harry Vincent, agent of The Shadow, alighted from a taxicab across the street from Rodney Paget’s apartment house. He strolled toward the side of the building and looked upward toward the lighted windows.

He made a careful calculation. He discovered one particular window — the living-room window of Paget’s apartment. The window was lighted.

Harry returned to a vantage point, from which he could watch the door of the apartment house. He waited patiently for nearly ten minutes. A man came slowly along the street and stopped a few feet away.

“Harry,” said a low voice.