“Oh yes, that’s right,” said Mr. Martin, completely reassured. “Thank you, my dear, I’ll see that either Mr. Lacey or myself brings you back the key so that your uncle’s men may get in on Monday morning. That’s the shop, there, isn’t it?”

He waited until the child had disappeared into the shop, then opened the door of Number 407 with the key which she had given him, walked in and closed the door behind him. Here he paused for a moment, thinking rapidly. He felt that he was up against a brain as agile as his own, and that the coming interview would demand all his skill if he were to bring it to a favourable issue. This man Lacey had taken steps to advertise the fact that Mr. Martin had entered the premises, obviously as a precaution against foul play. His automatic would be of no use to him, he would have to rely upon his brains instead.