“She did.”
“Her second motive,” Holmes went on, “was hatred, a virulent and consuming hatred for the man to whom she was married.”
“You can’t possibly know that,” John snapped at him. “You’re guessing again.”
“I do not make guesses. Mrs. Costain’s hatred of her husband was apparent to me at Dr. Axminster’s dinner party Tuesday evening. My eyes are trained to examine faces and not their trimmings-that is to say, their public pose. As for proof of her true feelings, and of her guilt, I discovered the first clue shortly after you and I found Andrew Costain’s corpse.”
“What clue?”
“Face powder, of course.”
“Eh? Face powder?”
“When I examined the wound in Costain’s back through my glass, I discovered a tiny smear of the substance on the cloth of his coat-the same type and shade as worn by Mrs. Costain. Surely you noticed it as well, Quincannon?”
“Yes, yes,” John said. But his tone and the way he fluffed his whiskers told Sabina that if he had noticed the smear, he’d failed to correctly interpret its meaning. “But I don’t see how that proves her guilt. They were married … her face powder might have gotten on his coat at any time, in a dozen different ways.”
“I beg to differ,” the Englishman said. “It was close and to the right of the wound, which indicated that the residue must have adhered to the murderer’s hand when the fatal blow was struck. It was also caked and deeply imbedded in the fibers of the cloth. This fact, combined with the depth of the wound itself, further indicated that the blade was plunged into Costain’s flesh with great force and fury. An act born of hatred as well as greed. The wound itself afforded additional proof. It had been made by a stiletto, hardly the type of weapon a professional pannyman such as Dodger Brown would carry. A stiletto, furthermore, as my researches into crime have borne out, is much more a woman’s weapon than a man’s.”
There was no way in which John could refute this logic, and it was plain that he knew it. He sat down in the chair Holmes had vacated and wisely held his tongue.
Penelope Costain once again claimed coldly outraged innocence. No one except Sabina paid her any attention, least of all John and the Englishman. The woman’s controlled bluster was a marvel to behold.
“Now then,” Holmes continued, “we have the mystery of Mrs. Costain’s actions after striking the death blow. Her evidently miraculous escape from the house, only to reappear later dressed in evening clothes.” He directed a keen look at John. “Of course you know how this bit of flummery was managed.”
“Of course.” But John finger-combed his whiskers again as he spoke.
“Pray elaborate.”
“There is little enough mystery in what she did. She simply hid until you and I were both inside the study and then slipped out through one of the windows. She could easily have prepared one in advance so that it slid up and down noiselessly, and also loosened its latch just enough to allow it to drop back into the locking bracket after she climbed through and lowered the sash. The window would then appear to have been unbreached.”
“Ingenious.”
“She may have thought so.”
“I meant your interpretation,” Holmes said. “Unfortunately, however, you are wrong. That is not what she did.”
“The devil you say!”
“Quite wrong on all counts except that she did, in fact, hide for a length of time. She could not have foreseen that both front and rear doors would be blocked. If simple escape had been the plan, she could reasonably have expected to slip out by either the front or rear door, thus obviating use of a window. Nor could she be certain in advance that a loosened window latch would drop back into its bracket and thus go unnoticed. Nor could she be certain that we would fail to hear her raising and lowering the sash, and capture her before she could vanish into the night.”
John said heavily, “I suppose you have a better theory.”
“Not a theory, the exact truth of the matter. Her hiding place was the very same one she and her husband had decided upon as part of the original scheme. I discovered it yesterday afternoon when I returned to the Costain home while Mrs. Costain was away and conducted a careful search of the premises.”
“Unlawful trespass!” This time, Penelope Costain’s outrage was not feigned. She appealed to the heavyset Prussian policeman. “I caught him there, Inspector, and you heard him admit to the fact. I demand that you arrest him.”
“It’s a little late for that, Mrs. Costain,” Kleinhoffer said. “Let’s hear the rest of what the limey … what Mr. Holmes has to say.”
“Thank you, Inspector. I expect that under the circumstances, you’ll agree that my actions were justified.”
“Maybe. If you can explain how she got out of the house.”
“She didn’t. She never left it.”
“What’s that? Never left it?”
Holmes paused as John had done earlier, for dramatic effect. “When you have eliminated the impossible,” he said, “whatever is left must, perforce, be the truth. As applied in this case, I concluded-as Mr. Quincannon did-that it was impossible for Andrew Costain’s slayer to have committed murder in and then escape from the locked study. Therefore Costain could not have been locked in when the stiletto was plunged into his body. I further concluded that it was impossible for the slayer to have escaped from the house after the crime was committed. Therefore she did not escape from it. Penelope Costain was hidden on the premises the entire time.”
Kleinhoffer demanded to know where. “You and Quincannon searched the house from top to bottom, and so did my men. Somebody would’ve found her if she was there.”
“But she was and no one did. Consider this: strangers cannot possibly know every nook and cranny in a large old home in which they have never before set foot. The owners, however, are fully intimate with every inch of their property.”
“True enough,” Pollard interjected, “but a place large enough for a woman to hide…”
“Indeed. And the Costain home contains just such a place. During my search, I discovered a tiny nook inside the kitchen pantry where preserves and the like are stored. The entrance is hidden by the stocked pantry shelves in front of it, so that the Costains could be reasonably sure it would be overlooked by strangers. The nook itself is some four feet square, and while it has no ventilation, its door when cracked open permits enough air for normal breathing.”
Sabina remembered the smudge of dirt on the Englishman’s cheek she’d noticed yesterday. Her thought at the time had been correct: he really had been crawling around in dark corners. She couldn’t help but admire his tenacity. And his cunning deductive powers, which really were quite remarkable.
“Mrs. Costain had no trouble remaining hidden for well over an hour,” Holmes went on, “ample time for her to change from the dark male clothing into evening clothes she had placed in the nook earlier. After the arrival of the police, when none of the officers was in the immediate vicinity, she slipped out through the kitchen and dining room to the front hallway and pretended to have just arrived home. The first person to encounter her-Sergeant Mahoney, I believe-had no reason to doubt her story.”
John said moodily, “But you did, I suppose.”
“Oh, quite. When she first entered the study, I observed the remnants of cobwebs and traces of dust on the hem of her skirt, the fur of her wrap, even the ostrich plume in her chapeau. The pantry room contains cobwebs, dust, and dirt of the same sort. I also observed that a fragment had been torn from one of her fingernails, leaving a tiny wound in the cuticle. Earlier, during my studies of the hallway carpet, I found that same tiny piece, stained with a spot of fresh blood-broken off, of course, when she stabbed her husband. Quod erat demonstrandum.”
Penelope Costain said, “There’s no proof of any of this.”
“Ah, but there is. When Inspector Kleinhoffer consults with Sergeant Mahoney and the officers who were stationed outside your home on that fateful night, I have no doubt that all will swear an oath that no conveyance arrived and no one entered the house through the front or rear doors. As for the missing jewelry and coins, and the murder weapon…” He shifted his gaze to Kleinhoffer. “You’ll find them where she hid them, Inspector-in a bag of sugar on a shelf in the pantry nook.”