Keats moved even closer.
“Once you saw what you had to do,” continued Ellery, “you realized that you were seriously handicapped. You couldn’t come and go as you pleased; you had no mobility. An ordinary murder was out of the question. Of course, you could have disposed of Hill right in this room during a business conference by a shot. But Hill’s death wasn’t the primary objective. He had to die and leave you free to run the business.
“You had to be able to kill him in such a way that you wouldn’t be even suspected.
“It occurred to you, as it’s occurred to murderers before, that the most effective way of diverting suspicion from yourself was to create the illusion that you were equally in danger of losing your life, and from the same source. In other words, you had to create a fictitious outside threat directed not merely at Hill but at both of you.
“Your and Hill’s connection with Charles Lyell Adam twenty-five years ago provided a suitable, if daring and dangerous, means for creating such an illusion. If Adam were ‘alive,’ he could have a believable motive to seek the death of both of you. Adam’s background could be traced by the authorities; the dramatic voyage of the Beagle was traceable to the point of its disappearance with all hands; the facts of your and Hill’s existence and present situation in life, plus the hints you could let drop in ‘Adam’s’ note, would lead any competent investigator to the conclusion you wanted him to reach.
“You were very clever, Priam. You avoided the psychological error of making things too obvious. You deliberately told not quite enough in ‘Adam’s’ note. You repeatedly refused on demand to give any information that would help the police or make the investigation easier, although an examination of your ‘refusals’ show that you actually helped us consider-ably. But on the surface you made us work for what we got.
“You made us work hard, because you laid a fantastic trail for us to follow.
“But if your theory-of-evolution pattern was on the fancy side, your logic was made curiously more convincing because of it. To nurse a desire for revenge for almost a generation a man has to be a little cracked. Such a mind might easily run to the involved and the fanciful. At the same time, ‘Adam’ would naturally tend to think in terms of his own background and experience. Adam having been a naturalist, you created a trail such as an eccentric naturalist might leave ― a trail you were sure we would sooner or later recognize and follow to its conclusion, which was that Naturalist Charles Adam was ‘the enemy out of the past.’
“Your camouflage was brilliantly conceived and stroked on, Priam. You laid it so thickly on this case that, if you had not foolishly used that broken-T typewriter, we should probably have been satisfied to pin the crime on a man who’s really been dead for a quarter of a century.” Priam’s big head wavered a little, almost a nod. But it might have been a momentary trembling of the muscles of his neck. Otherwise, he gave no sign that he was even listening.
“In an odd sort of way, Priam, you were unlucky. You didn’t realize quite how bad Hill’s heart was, or you miscalculated the impact of your paper bullet. Because Hill died as a result of your very first warning. You had sent yourself a warning on the same morning, intending to divide the other warnings between you and Hill, probably, alternating them. When Hill died so immediately, it was too late to pull yourself out. You were in the position of the general who has planned a complicated battle against the enemy, finds that his very first sortie has accomplished his entire objective, but is powerless to stop his orders and preparation for the succeeding attacks. Had you stopped after sending yourself only one warning the mere stoppage would have been suspect. The warnings to yourself had to continue in order that the illusion of Adam-frightening-Hill-to-death should be completely credible.