They reached at length a small dilapidated square.The houses there had a sinister air in the midst of their dirt and decay. Boris looked round, and Tommy drew back into the shelter of a friendly porch. The place was almost deserted. It was a cul-de-sac, and consequently no traffic passed that way. The stealthy way the other had looked round stimulated Tommy's imagination.From the shelter of the doorway he watched him go up the steps of a particularly evil-looking house and rap sharply, with a peculiar rhythm, on the door. It was opened promptly, he said a word or two to the doorkeeper, then passed inside. The door was shut to again.