For ten minutes a deep unbroken hush brooded over the neighbourhood. If there were any human beings about they still remained silent and invisible, while the solitary cat, who had glanced up resentfully as Bugg passed, gradually resumed her former attitude of somnolent repose. Then once more the door of number sixteen opened, and Tony and Isabel made their appearance. The latter was wearing no hat, and her red-gold hair gleamed in the sunshine, like copper in the firelight. They strolled down together as far as the gate, where they remained for a few moments laughing and chatting. Then, with a final and fairly audible observation to the effect that he would be back about six, Tony took his departure. He went off to the left, in the opposite direction from that patronized by Bugg. Turning lightly round Isabel sauntered back up the garden. The front door closed behind her, and once again peace--the well ordered peace of a superior London suburb, descended upon Latimer Lane. * * * * * * * At the back of the house Mrs. Spalding was standing at the kitchen window, which she had pushed up to its fullest extent. Her eyes were fixed anxiously upon the summit of the wall which divided her miniature back yard from the adjoining property. It was a venerable wall, of early Victorian origin, about twelve feet in height, and thickly covered with a mat of ivy. At last, from the other side came a faint rustle, followed almost immediately by the unmistakable scrape and scuffle of somebody attempting an ascent. Then a hand and arm appeared over the top, and a moment later Bugg had hoisted himself into view, and was sitting astride the parapet. He paused for an instant to whisper back some hoarse but inaudible remark, and then catching hold of the ivy swung himself neatly and rapidly to the ground. There was another and rather louder scuffle, and Tony followed suit. He came down into the yard even quicker than Bugg--his descent being somewhat accelerated by the behaviour of a branch of ivy, which detached itself from the wall, just as he had got his full weight on it. "Yer ain't 'urt yerself, 'ave ye, sir?" inquired the faithful "Tiger" with some anxiety. Tony shook his head, and discarded the handful of foliage that he was still clutching. "One should never trust entirely to Nature, Bugg," he observed. "She invariably lets one down." He stopped to flick off the dust and cobwebs from the knees of his trousers, and then leading the way across the yard to the kitchen window, he scrambled in over the sill. "I am afraid I have thinned out your ivy a bit, Mrs. Spalding," he remarked regretfully. "It doesn't matter the least about that, sir," replied Mrs. Spalding, "so long as you haven't gone and shook yourself up." "I don't think I have," said Tony. "I feel extraordinarily well except for a slight craving for tea." He paused. "No sign of the enemy yet, I suppose?"