But, deriving courage from the fact that four days had elapsed without anything happening, Mr. Copperdock refused to consider any such proposal. He must have detected the general scepticism with which his story of the finding of the counter had been received, and had resolved to say no more about it. He went to the Cambridge Arms at his usual hour, stayed there until closing time, and was then accompanied home by two friends of his, who lived in the Edgware Road, and who had to pass the door on their way home. He invited these two to come in and have a last drink with him, and they accepted, on the grounds that it was a beautiful night, and very thirsty work walking. The story of the finding of the counter was by this time familiar to all the clientele of the Cambridge Arms, each individual member of which suspected some other member of having somehow conveyed it into Mr. Copperdock’s possession. It was absurd to think, as one of them remarked in his absence, that anybody could have a grudge against Sam Copperdock. Somebody must be pulling his leg, that was the only possible explanation. It was with some considerable interest, therefore, that his two friends followed the tobacconist as he took them into his bedroom and showed them the exact place where he found the counter. It was not until nearly eleven that Mr. Copperdock’s party broke up. Inspector Whyland’s deputy, strolling past on the other side of the road, noticed the parting on the doorstep, and observed that after the departure of his friends, Mr. Copperdock shut the door of his shop. A few minutes later he saw a light switched on in one of the front rooms upstairs. This he knew, from his experience of previous nights, was the signal that Mr. Copperdock was going to bed. Mr. Ludgrove, since the tobacconist had refused his offer of hospitality, spent the evening by himself. The room above his shop was littered with innumerable boxes containing all manner of dried herbs and similar items of the stock-in-trade of his calling. He spent several hours between that room and his sanctum. His work bench became strewed with specimens to which from time to time he affixed labels with high-sounding names. The door of his shop was ajar until about half-past ten, up till which hour an occasional customer interrupted his labours. After that time it was closed, and he was able to devote his whole attention to his plants. He was still working at midnight. He appeared to require very little sleep, and rarely went to bed before the early hours of the morning. He had just brewed himself a cup of his favourite cocoa, when suddenly he heard a violent hammering upon the door of the shop. Instinctively he glanced at the clock upon the mantelpiece. The hands pointed to twenty minutes past twelve.