During the lull Karlov matured his plans, then resumed operations, calculating that he would have some forty-odd hours' leeway.
His agent was clever.

He had followed Kitty from Eightieth Street to the Knickerbocker Hotel.

There he had lost her.

He had loitered on the sidewalk until midnight, and was then convinced that the girl had slipped by.

So he had returned to Eightieth Street; but as late as five in the morning she had not returned.
This agent had followed the banker after his visit to Kitty.