Stutsman ducked into an alley where even deeper darkness lay. Russ, with a delicate adjustment, slid the televisor along, closer to Stutsman, determined not to lose sight of him for an instant.

The man suddenly turned into a doorway so black that nothing could be seen. Sounds of sharp, impatient rappings came out of the screen as Stutsman struck the door with his stick.

Brilliant illumination sprang out over the doorway, but Stutsman seemed not to see it, went on knocking. The colors on the screen were peculiarly distorted.

"Ultra-violet,” grunted Greg. “Whoever he's calling on wants to have a good look before letting anybody in."

The door creaked open and a shaft of normal light spewed out into the street, turning its murkiness to pallid yellow.

Stutsman stepped inside.

The man at the door jerked his head. “Back room,” he said.

* * *

The televisor slid through the door into the lighted room behind Stutsman. Dust lay thick on the woodwork and floors. Patches of plaster had broken away. Furrows zig-zagged across the floor, marking the path of heavy boxes or furniture which had been pushed along in utter disdain of the flooring. Cheap wall-paper hung in tatters from the walls, streaked with water from some broken pipe.

But the back room was a startling contrast to the first. Rich, comfortable furniture filled it. The floor was covered with a steel-cloth rug and steel-cloth hangings, colorfully painted, hid the walls.