"All the same," she remarked, "I am not at all sure that was the case with Captain Graham's invention. There were rumours for days before that something wonderful was happening on Salisbury Plain. They had to cover up whole acres of ground after his last experiments, and a man who was down there told me that it seemed just as though the life had been sucked out of it." "Where did you collect all this information?" her visitor inquired. She shrugged her shoulders. "One hears everything in London." Lutchester was sitting with his finger-tips pressed together. For a moment his attention seemed fixed upon them. "There are things," he said, "which one hears, too, in the far corners of the world--on the Atlantic, for instance." "You have had some news?" she interrupted. "It is really a private piece of information," he told her, "and it won't be in the papers--not the way the thing happened, anyway--but I don't suppose there's any harm in telling you, as we were both more or less mixed up in the affair. Graham was shot the next day, on his way up to Northumberland." "Shot?" she exclaimed incredulously. "Murdered, if you'd like the whole thrill," Lutchester continued. "Of course, we didn't get many particulars in the wireless, but we gathered that he was shot by some one passing him in a more powerful car on a lonely stretch of the Great North Road." Pamela shuddered. She was for the moment profoundly impressed. A certain air of unreality which had hung over the events of that night was suddenly banished. The whole tragedy rose up before her eyes. The effect of it was almost stupefying. "Gave me quite a shock," Lutchester confided. "Somehow or other I had never been able to take that night quite seriously. There was more than a dash of melodrama in it, wasn't there? Seems now as though those fellows must have been in earnest, though." "And as though Captain Graham's formula," she reminded him gravely, "was the real thing." "Whereupon," Lutchester observed, "our first interest in the affair receives a certain stimulus. Some one stole the formula. To judge from the behaviour of those amiable gentlemen connected with Henry's Restaurant, it wasn't they. Some one had been before them. Have you any theories, Miss Van Teyl?" "I can tell you who has," she replied. "Do you remember when we were all grouped around that notice--Mefiez-vous! Taisez-vous! Les oreilles ennemies vous ecoutent!?" "Of course I do," he assented. "Do you remember Baron Sunyea making a remark afterwards? He had been standing by and heard everything Graham said." "Can't say that I do," Lutchester regretted, "but I remember seeing him about the place." "You promise to say or do nothing without my permission, if I tell you something?" she went on. "Naturally!"