Joan left at each Club a message asking Walter Brooklyn to ring her up at Liskeard House immediately he came in. This was all that could be done for the moment; and to Liskeard House they returned, having suffered a check at the outset of their quest. Ellery promised to spend the evening scouring London for traces of Walter Brooklyn; and in the mind of each was the half-formed thought that he might have fled rather than reveal what he knew. Each knew that the other feared this; but neither put the thought into words. They arranged to meet again on the following morning, and Ellery was to ring up later in the evening to report whether he had traced Walter, and to hear whether any message had come to Joan from either of the Clubs. Then, after the manner of lovers, they bade each other farewell a dozen times over, each farewell more lingering than the last. At length Ellery went; for he was due at Scotland Yard, where he hoped to find that his _alibi_ had been accepted, and the last trace of suspicion removed from him. It would be awkward to be followed about by the man in police boots wherever he went with Joan, and it would be awkward to have the police know exactly what they were doing in Walter Brooklyn’s interest. The police boots had followed Joan and him on their visits to the two Clubs, and now, as he left Liskeard House, Ellery saw their owner leaning against a lamp-post opposite, and gazing straight at the front door. Never, he thought, had a man looked more obviously a detective—or rather a policeman in plain clothes. Even apart from the boots, he was labelled policeman all over—from his measured stride to the tips of his waxed moustache. As Ellery turned down into Piccadilly, he heard the man coming along behind him. Chapter XV To and Fro