Also, Burton was late for his appointment, for that must have been Burton--business such as old Isaac had in hand that night would have permitted the entrance of no other visitor but K.
Wilmington Maddon's private secretary.
He moved down the lane to the door, and tried it softly.

It was locked, of course.

The slim, tapering, sensitive fingers, whose tips were eyes and ears to Jimmie Dale, felt over the lock--and a slender little steel instrument slipped into the keyhole.

A moment more and the catch was released, and the door, under his hand, began to open.

With it ajar, he paused, his eyes searching intently up and down the lane.