quired Coombes in muffled tones from the top of
the wall.

"No," rapped Kerry. "Hide the ladder again. If I want help I'll whistle.
Catch!"

He tossed the jemmy up to Coombes, and Coombes succeeded in catching it.
Then Kerry raised the glass-less sash of the window and stepped into a
little room, which he surveyed by the light of his electric torch. It
was filthy and littered with rubbish, but showed no sign of having been
occupied for a long time. The ceiling was nearly black, and so were the
walls. He went out into a narrow passage similar to that in the house of
Sin Sin Wa and leading to a stair.

Walking quietly, he began to ascend. Mollie Gretna's description of the
opium-house had been most detailed and lurid, and he was prepared for
some extravagant scene.

He found three bare, dirty rooms, having all the windows boarded up.

"Hell!" he said succinctly.

Resting his torch upon a dust-coated ledge of the room, which
presumably was situated in the front of the house, he deposited a cud of
chewing-gum in the empty grate and lovingly selected a fresh piece from
the packet which he always carried. Once more chewing he returned to the
narrow passage, which he knew must be that in which the secret doorway
had opened.

It was uncarpeted and dirty, and the walls were covered with faded
filthy paper, the original color and design of which were quite lost.
There was not the slightest evidence that a door had ever existed in any
part of the wall. Following a detailed examination Kerry returned his
magnifying glass to the washleather bag and the bag to his waistcoat
pocket.

"H'm," he said, thinking aloud, "Sin Sin Wa may have only one eye, but
it's a good eye."

He raised his glance to the blackened ceiling of the passage, and saw
that the trap giving access to the roof was situated immediately above
him. He directed the ray of the torch upon it. In the next moment he had
snapped off the light and was creeping silently towards the door of the
front room.

The trap had moved slightly!

Gaining the doorway, Kerry stood just inside the room and waited. He
became conscious of a kind of joyous excitement, which claimed him at
such moments; an eagerness and a lust of action. But he stood perfectly
still, listening and waiting.

There came a faint creaking sound, and a new damp chilliness was added
to the stale atmosphere of the passage. Someone had quietly raised the
trap.

Cutting through the blackness like a s