Passing cars, sloshing through the muck, cast moving silhouettes upon the sidewalk and the wall of the house.
Black depths surrounded the steps of the building; and it was from this murky umbra that a shadow seemed to rise and blot out the door of the house.
In a moment, the blackness was gone, and no sign of it remained. Inside the rooming house, however, a singular phenomenon occurred.
The landlady, coming along the hall beside the stairs, stopped for a moment, startled by a peculiar gloom that seemed to flit toward the steps that led to the second floor. Then she realized that her imagination must be tricking her.
Quelling her alarm, she locked the front door, and went upstairs.
A new door had been placed in the entrance to the room where Frank Jarnow had been murdered. Had Mrs. Johnson come up the stairs ten seconds sooner, she would have been keenly startled. For there was a sharp click in the lock of the door, and the barrier had opened inward. But, an instant before the landlady turned at the top of the stairs, the door had closed silently.
The sight of the door made the woman pause. For a moment she listened instinctively outside the room, imagining that some one might be within. Hearing no sound, she passed on.
Within the room, a being moved. So stealthy were his steps that they were soundless, even though the carpet was thin and worn.
The invisible visitor moved here and there, from door to window. Satisfied that the shade was down, he made his presence known by the thin ray of a tiny flashlight.
First the illumination fell upon the table, which still was in its same position under the hanging lamp. The quiet investigator could not be seen; only the beam of his light indicated his presence.