She was imprisoned by the Hands.

She was in their power, and up till now they had shown themselves ruthless enough.
A room with a roof window only! How could she define her whereabouts! His first impulse was to rush madly out into the street and search for her.
Then his common sense intervened.

His one hope was through Craig.

Again he took up his vigil in front of the window.

Once more his eyes swept the narrow street with its constant stream of passers-by.