Prokop stepped aboard. It never occurred to him that he was riding in the same cab that he had left. One does not observe the distinctive features of a taxicab.
Prokop left the cab after a short ride, and walked briskly toward the apartment house where he lived. He entered the door, and let it close behind him.
He glanced back as he did so; but saw nothing but the deep shadows of the entrance. He rode up in the automatic elevator.
It was not on the ground floor when he pushed the button. Prokop did not see the shadowy form that moved silently up the stairway to the second floor.
When the elevator stopped at the third floor, Prokop was in no hurry. He went slowly down the hall, not looking behind him; hence he did not see the motion that occurred in the shadowy landing at the top of the stairway.
A few minutes later, a taxi driver was standing in the entrance to the apartment house. He checked the number of Prokop’s apartment with the name that appeared beside it — Henry Propert.
Then the cabman left the building. He turned the corner, and reached his cab. He stepped in back, and placed a black bundle beneath the seat. Then he drove toward the center of Manhattan.
He picked up a passenger on the way, and left the man at his destination, near Forty-second Street and Broadway. The passenger paid very little notice to the driver when he paid his fare.
He had not the slightest suspicion that the man who had driven him was the most mysterious personage in New York — that master of detection whose name carried fear to the hordes of gangland — The Shadow!