"One learns prudence by experience," said Madame sagely. She was scarcely to know, poor lady, that even as she uttered this trite aphorism, under cover of darkness and his hat, Mr Carrados had just ruined his signet ring by blazoning a golden "7" upon her garden step to establish its identity if need be. A cul-de-sac that numbered from the closed end seemed to demand some investigation. "Seldom," he replied to her remark. "One goes on taking risks. So we are there?" Madame Ferraja had opened the front door with a latchkey. She dropped the latch and led Carrados forward along the narrow hall. The room they entered was at the back of the house, and from the position of the road it therefore overlooked the park. Again the door was locked behind them. "The celebrated Mr Carrados!" announced Madame Ferraja, with a sparkle of triumph in her voice. She waved her hand towards a lean, dark man who had stood beside the door as they entered. "My husband." "Beneath our poor roof in the most fraternal manner," commented the dark man, in the same derisive spirit. "But it is wonderful." "The even more celebrated Monsieur Dompierre, unless I am mistaken?" retorted Carrados blandly. "I bow on our first real meeting." "You knew!" exclaimed the Dompierre of the earlier incident incredulously. "Stoker, you were right and I owe you a hundred lire. Who recognized you, Nina?" "How should I know?" demanded the real Madame Dompierre crossly. "This blind man himself, by chance." "You pay a poor compliment to your charming wife's personality to imagine that one could forget her so soon," put in Carrados. "And you a Frenchman, Dompierre!" "You knew, Monsieur Carrados," reiterated Dompierre, "and yet you ventured here. You are either a fool or a hero." "An enthusiast--it is the same thing as both," interposed the lady. "What did I tell you? What did it matter if he recognized? You see?" "Surely you exaggerate, Monsieur Dompierre," contributed Carrados. "I may yet pay tribute to your industry. Perhaps I regret the circumstance and the necessity but I am here to make the best of it. Let me see the things Madame has spoken of, and then we can consider the detail of their price, either for myself or on behalf of others." There was no immediate reply. From Dompierre came a saturnine chuckle and from Madame Dompierre a titter that accompanied a grimace. For one of the rare occasions in his life Carrados found himself wholly out of touch with the atmosphere of the situation. Instinctively he turned his face towards the other occupant of the room, the man addressed as "Stoker," whom he knew to be standing near the window. "This unfortunate business _has_ brought me an introduction," said a familiar voice. For one dreadful moment the universe stood still round Carrados. Then, with the crash and grind of overwhelming mental tumult, the whole strategy revealed itself, like the sections of a gigantic puzzle falling into place before his eyes.