"Don't let that man get out!" he cried. "Good Lord! I've only just remembered. You say you found me breaking into the safe! You say you heard a noise and came down to investigate! Well, then, what's that test-tube of the explosive doing in your breast-pocket?" He swung round to Miss Trimble. "You needn't take my word or his word. There's a much simpler way of finding out who's the real crook. Search us both." He began to turn out his pockets rapidly. "Look here--and here--and here! Now ask him to do the same!" He was pleased to observe a spasm pass across Gentleman Jack's hitherto composed countenance. Miss Trimble was eyeing the latter with sudden suspicion. "Thasso!" she said. "Say, Bill, I've f'gott'n y'r name--'sup to you to show us! Less've a look 't what y' got inside there." Gentleman Jack drew himself up haughtily. "I really could not agree to--" Mrs. Pett interrupted indignantly. "I never heard of such a thing! Lord Wisbeach is an old friend--" "Less'f it!" ordered Miss Trimble, whose left eye was now like the left eye of a basilisk. "Y' _gotta_ show us, Bill, so b' quick 'bout 't!" A tired smile played over Gentleman Jack's face. He was the bored aristocrat, mutely protesting against something that "wasn't done." He dipped his slender fingers into his pocket. Then, drawing out the test-tube, and holding it up, he spoke with a drawling calm for which even Jimmy could not help admiring him. "All right! If I'm done, I'm done!" The sensation caused by his action and his words was of the kind usually described as profound. Mrs. Pett uttered a strangled shriek. Willie Partridge yelped like a dog. Sharp exclamations came simultaneously from each of the geniuses. Gentleman Jack waited for the clamour to subside. Then he resumed his gentle drawl. "But I'm not done," he explained. "I'm going out now through that window. And if anybody tries to stop me, it will be his--or her--" he bowed politely to Miss Trimble--"last act in the world. If any one makes a move to stop me, I shall drop this test-tube and blow the whole damned place to pieces." If his first speech had made a marked impression on his audience, his second paralysed them. A silence followed as of the tomb. Only the yapping of the dog Aida refused to be stilled. "Y' stay where y' are!" said Miss Trimble, as the speaker moved towards the window. She held the revolver poised, but for the first time that night--possibly for the first time in her life--she spoke irresolutely. Superbly competent woman though she was, here was a situation that baffled her. Gentleman Jack crossed the room slowly, the test-tube held aloft between fore-finger and thumb. He was level with Miss Trimble, who had lowered her revolver and had drawn to one side, plainly at a loss to know how to handle this unprecedented crisis, when the door flew open. For an instant the face of Howard Bemis, the poet, was visible. "Mrs. Pett, I have telephoned--" Then another voice interrupted him.