"Allen, though, went to pieces at our first question and confessed volubly that his crazy hatred of his three partners had made him plan a killing of them that all would think the Invisible Master's work. The funny thing, was, too, that each one of the three believed that the other two crimes had been really the Invisible Master's work!
"I was amazed, stupefied. If the Invisible Master had not committed those crimes, then his demand for the five millions was simply a gigantic bluff. Was there, then, any Invisible Master at all? Was there, the thought flashed over me for the first time, any such power of invisibility as Grantham claimed to have discovered? I boiled it all down and found that the only real evidence of the invisibility part of it was the demonstration Grantham had given. I grabbed all the books on optics I could find in an effort to learn whether such a demonstration could be faked, and soon found out about the tourmaline crystals and their remarkable property. It all fitted in exactly with the demonstration as it had been described to me. Grantham had made no demonstrations at all since that first one, nor had we dreamed of asking him for them, so utter was our belief in his word and in the Invisible Master's existence.
"I made some swift inquiries and the whole thing burst clear on me. There had never been any invisibility or any Invisible Master at all. Grantham had planned the great bluff that was to wring five millions out of the city, had built it up from the trick of that first demonstration and from the circumstantial evidence he was able to gather to support the thing, had used the crimes that inevitably resulted from the city's belief in the Invisible Master to make that belief even stronger. I drove out to the place where we were last night and it took but minutes of searching to find the concealed niche beside the stone where the money still lay.
"Undoubtedly Grantham meant to retrieve it later on, and undoubtedly he would have refused ever to give out any information or any demonstrations of his invisibility-method, by saying that he would take no chances on loosing another invisible criminal on the world. Gray would never have been found, and would then have been believed always the unseen criminal. Almost Grantham won, and would have won had not that one routine and unthinking step of mine defeated him. Yet he must have known, too, that there was always a chance of losing, for when I came out this morning after telling him over the phone to be waiting here for some new information I was bringing, he had the cyanide with him. And the rest—you saw how he took his one way out."
When Wade had finished Carton and Ellsworth gazed at him across the sunlit laboratory, spellbound. It was Carton who at last found his voice.
"And we never guessed—we never dreamed—that there was never any Invisible Master!"
Wade was looking thoughtfully out of the window. "Did I say there wasn't? I think I was wrong in that, after all—I think there was an Invisible Master whose hand has lain heavy on New York for these last days. Fear!—the fear that Grantham loosed on the city for his own ends, the fear that stalked its ways and was by day and night its unseen lord! It was that that was the true Invisible Master!"
THE END