As the clock upon the mantelpiece struck eleven, his eyes were at once lifted to the clock-face, and almost at once he moved from the lady to whom he was talking and made his way to the door. Mr. Mudge turned back to the window and pushed it still more open. It was a clear night of April, and April had brought with it the warmth of summer. Mr. Mudge stood at the open window facing the coolness and the quiet of the square; and thus by the accident of an overcrowded room he became the witness of a little episode which might almost have figured in some bygone comedy of intrigue. Callon passed through the line of carriages in the roadway beneath, and crossed the corner of the square to the pavement on the right-hand side. When he reached the pavement he walked for twenty yards or so in the direction of Piccadilly, until he came to a large and gloomy house. There a few shallow steps led from the pavement to the front door. Callon mounted the steps, rang the bell, and was admitted. There were a few lights in the upper windows and on the ground floor; but it was evident that there was no party at the house. Callon had run in to pay a visit. Mr. Mudge, who had watched this, as it were, the first scene in the comedy, distinctly heard the door close, and the sound somehow suggested to him that the time had come for him to go home to bed. He looked at his watch. It was exactly a quarter past eleven--exactly, in a word, three-quarters of an hour since Tony Stretton, who "had something else to do," had taken his leave of his friend Chase in Stepney. Mr. Mudge turned from the window to make his way to the door, and came face to face with Pamela and Alan Warrisden. Pamela spoke to him. He had never yet met Warrisden, and he was now introduced. All three stood and talked together for a few minutes by the open window. Then Mudge, in that spirit of curiosity which Callon always provoked in him, asked abruptly-- "By the way, Miss Mardale, do you happen to know who lives in that house?" and he pointed across the corner of the square to the house into which Callon had disappeared. Pamela and Warrisden looked quickly at one another. Then Pamela turned with great interest to Mr. Mudge. "Yes, we both know," she answered. "Why do you ask?" "Well, I don't know," said Mudge; "I think that I should like to know." The glance which his two companions had exchanged, and Pamela's rather eager question, had quickened his curiosity. But he got no answer for a few moments. Both Pamela and Warrisden were looking out towards the house. They were standing side by side. Mr. Mudge had an intuition that the same thought was passing through both their minds. "That is where the truants lived last July," said Warrisden, in a low voice. He spoke to Pamela, not to Mr. Mudge at all, whose existence seemed for the moment to have been clean forgotten.