into the house and mounted the ramshackle staircase. Everything
in the house was filthy beyond words. The grimy paper, of a
pattern now indistinguishable, hung in loose festoons from the
wall. In every angle was a grey mass of cobweb.

Tommy proceeded leisurely. By the time he reached the bend of
the staircase, he had heard the man below disappear into a back
room. Clearly no suspicion attached to him as yet. To come to
the house and ask for "Mr. Brown" appeared indeed to be a
reasonable and natural proceeding.

At the top of the stairs Tommy halted to consider his next move.
In front of him ran a narrow passage, with doors opening on
either side of it. From the one nearest him on the left came a
low murmur of voices. It was this room which he had been
directed to enter. But what held his glance fascinated was a
small recess immediately on his right, half concealed by a torn
velvet curtain. It was directly opposite the left-handed door
and, owing to its angle, it also commanded a good view of the
upper part of the staircase. As a hiding-place for one or, at a
pinch, two men, it was ideal, being about two feet deep and three
feet wide. It attracted Tommy mightily. He thought things over
in his usual slow and steady way, deciding that the mention of
"Mr. Brown" was not a request for an individual, but in all
probability a password used by the gang. His lucky use of it had
gained him admission. So far he had aroused no suspicion. But he
must decide quickly on his next step.

Suppose he were boldly to enter the room on the left of the
passage. Would the mere fact of his having been admitted to the