Although we now switch to Mary's point of view, the best lines are still lifted directly from ACD's text and are in italics. Please excuse my complete lack of medical knowledge. All I know is what I find on the internet!

000

Mary pulled away from her impulsive hug and tried to control her trembling. The roller coaster of emotion he had forced her to ride upon that day was exhausting—from the initial jolt of adrenaline at the time of Mrs. Hudson's tearful phone call, to her gradual realization that this was not the dramatic exaggeration of the landlady's motherly concern, to the despairing acceptance that she might be about to lose a beloved friend. And now to find it had all been a trick! She was both bitterly hurt by his deception and infuriated at being so used by him.

"If you had only stayed back as I requested," Sherlock was admonishing her, "we could be well on the way to wrapping up the case by now. John would have done as I asked," he added, visibly aggrieved by her uncooperative nature.

"Well, I'm not John, am I? John chooses to think the best of you," Mary informed him impatiently. "He wants to believe you'd never tell him a lie."

"He'd have forgiven me. It's for a case," Sherlock insisted petulantly.

Before Mary could respond, her phone vibrated. "It's John," she announced, turning accusing eyes to his. She hated having caused John needless worry. She would have to put a good face on the situation. Didn't he already have his hands full with Harry being so intractable?" "Hullo, darling," she said calmly into the phone.

"I just got your message. What's going on?" John demanded, sounding concerned.

"A false alarm, Captain," she reassured him. "Sherlock's being a thoughtless, annoying prat, but what else is new? I have things well in hand."

"What's he done now?" John sighed, weariness in his tone.

"I'm not exactly sure yet, but I'm going to get to the bottom of it presently, and then I'll call you back and tell you all," Mary told him grimly.

"Shall I come home and help you dispose of the body?" he asked, understanding her tone.

She chuckled at that. "No, I've already decided to dismember him and bury him under the floor in 221C," she informed him.

"Well, you know best," he replied agreeably. "I trust your judgement entirely."

His familiar voice made her long for the comfort of his arms. "I miss you," she whispered.

"I'll be home soon," he promised. "I'll have Harry sorted before too much longer."

After a few more endearments, which caused a good deal of eye-rolling on Sherlock's part, she hung up and turned on him. "Get up and put something on," she commanded him, waving her right index finger in his face. "I can't talk to you seriously while you're lying in bed. I'm going to go down and relieve Mrs. Hudson's mind, and when I come back up we're going to have a conversation."

After informing the kindly landlady of the truth and persuading her to lie down with a cold compress on her head, Mary marched back upstairs to battle. She was gratified to see the detective had pulled a dressing gown on over his inside-out T-shirt and pyjama bottoms and was slumped in his leather armchair with an air of gloomy impatience surrounding him. The make-up he had artfully applied to make himself appear feverish and emaciated was still distorting his facial features and made her shake again with fury.

"Mary, time is of the essence," he began in his most commanding voice, obviously trying to regain control of the situation. She knew better than to allow him to think he could get the upper hand under any circumstances.

"You just sit there and think about what you've done," she told him, choosing to treat him like an errant schoolboy. "I can't deal with you until I've had some tea."

The very act of making tea calmed her raveled nerves and she felt fit to face him at last. Pointedly not offering him a cup, she curled up in John's armchair and said imperiously, "Speak."

"This is John's fault, you know. He started me on this line of inquiry," Sherlock began.

"John is completely faultless; this is entirely your own doing," Mary corrected him, perhaps a bit biased.

Ignoring her interruption, Sherlock continued. "The day before you left for Dublin, John pointed out an article in the paper concerning the death of a young man called Victor Savage. It was reported that he had contracted Naegleria fowleri while traveling in America and died soon after his return. John was disgusted with the faulty knowledge of the physician who treated the young man. 'The idiot seems to have no knowledge of geography,' he told me. 'This poor boy was a thousand miles away from any area in America that is affected by this amoeba.'"

Mary nodded. "He was obsessing about it that evening, when he ought to have been packing for Dublin," she agreed. "He said while the symptoms were vaguely similar to this disease, they were not identical; and the amoeba must be introduced through the nose, which would be impossible unless one were to bathe in water infested with it. He could not believe it possible for a reputable physician to have made such a mistake. He finally decided the newspaper was mistaken in its reporting. And the boy's only living relative seemed to be satisfied with the diagnosis, so no further investigation would be forthcoming."

"Yes, it was," Sherlock informed her. "I respect John's professional opinion over that of any other physician. I was certain he was right and set about to prove it. I discovered that this only living relative, an uncle called Culverton Smith, was involved in medical research and has a laboratory on his private estate. This man Smith has claimed to have found cures for a number of rare diseases, but his methods are considered so unorthodox and ill-conceived that no legitimate medical establishment will accept his research. I also discovered that Victor Savage, the son of Smith's sister, had inherited a great deal of money from his father and that he died intestate—all of his wealth automatically went to his only living relative."

"And Smith, I suppose, was in great need of money to continue his maverick research," Mary concluded.

"Exactly," Sherlock nodded, pleased that she was listening in spite of her injured feelings. "I broke into his laboratory and found a number of vials of rare and fatal diseases, one of which exactly matched the symptoms Savage had suffered. John was right—it was a strain of virus which is both deadly and rare, existing only in the jungles of Asia. It was obvious to me that Smith had caused his nephew to contract this dangerous disease upon his return from America in order to gain control of the young man's estate. He would, of course, have bribed his doctor to claim Savage's death was due to a disease he might have contracted in America.

"I then brought my suspicions to Lestrade, but although he tried several avenues of inquiry, without any legally obtained evidence we were stymied. Smith would not allow an autopsy, and their family physician was obstinately standing by his original diagnosis. Then Smith himself provided the answer."

"That Chinese puzzle box," Mary nodded. "I wondered what it was about it that made you scream like a scalded dog."

"I did not scream. I merely expressed my concern for your safety," Sherlock protested with excessive dignity.

"You screamed like a schoolgirl on the playground," Mary informed him, her dimples deepening with mischief.

Sherlock, with a long-suffering look, chose to ignore her teasing. "I had made no secret of my suspicions against Smith, even confronting him in person the second day of my investigations. So when a mysterious package appeared on the doorstep the next day, with no return address, it took no great leap of the imagination to deduce from whom it had come. I opened it with the greatest caution and found the Chinese puzzle box as you surmised. There were no fingerprints on it, which is in itself suspicious, and careful examination showed the presence of a sharp spring, like a viper's tooth, which emerges as you open it. I daresay it was by some such device that poor Savage was done to death."

"So you thought that, by pretending that Smith had really succeeded in his design, that you might surprise a confession," Mary concluded. "But in order to complete this deception, did you really feel you had to lie to me?"

"I never meant for you to be involved in any way, Mary," Sherlock said sincerely. "I am aware of your fear of loss, and I have promised John never to presume upon your courage in that area again. I knew your itinerary, that you were to have returned to work in the clinic today and that John expected to be here at his usual time this morning. This was perfect for my plan, as today is the fourth day after the box's arrival and Smith would expect me to be very near the end and suffering enough to permit a friend to call upon him for relief. When John didn't arrive, I asked Mrs. Hudson to call him. I was not aware that, being unable to reach him, she had taken it upon herself to call you. I would have stopped her, had I known."

"Is the fact that you had planned to lie only to John and Mrs. Hudson meant to make me feel happier about this strategy of yours?" Mary demanded, in a dangerous mood.

"Do you really think that John would be offended, Mary? You and he must both realize that among his many talents dissimulation finds no place," Sherlock returned earnestly. "If he shared my secret, he would never have been able to impress Smith with the urgent necessity of his presence, which was the vital point of the whole scheme. Knowing his vindictive nature, I was perfectly certain that Smith would come to look upon his handiwork. But I could not be the one to ask him to come. The request had to come from John, and Mrs. Hudson also had to be convincing as she let him into the house."

Mary considered this for a moment. "It's true that John has such a beautifully honest nature that he has no talent for deception," she agreed at last. "I don't agree with your methods, Sherlock, but I understand the thought process behind them. You've spent three days laying this trap for this despicable murderer. Give me his phone number and I'll complete your plan for you. No sense allowing him to escape justice because of my own offended sensibilities."

Sherlock now looked perplexed. "You want to help me? But you said you hated me," he said wonderingly.

She glared at him. "Oh, I do! Intensely! I expect I shall for a good part of the day. But I hate this murdering, inhuman monster who was trying to kill you even more. I want him in prison as much as you do. Let me call him and we'll get this over with."

The detective was still all at sea. "But Mary, you never lie," he reminded her.

"True. But that doesn't mean I'm incapable of it. On the contrary, I long ago abandoned the dark side and determined to use my powers only for good," Mary smiled.

Sherlock frowned. "Your powers?"

"With great power comes great responsibility," Mary informed him.

Sherlock looked as if she were speaking in an unknown tongue.

Mary sighed. "I don't lie because I'm bloody good at it," she explained plainly. "If you need someone who is an expert in dissimulation, I'm your girl."

Sherlock's lips curved into a pleased grin.

"However," Mary continued sternly, "you are still in deep waters. Don't you think you're getting away with this! You will pay for what you've done to me and Mrs. Hudson, as soon as this case is solved."

Sherlock's smile disappeared, replaced by a look of chagrin.

000

Kudos to anyone who notices the quotes from Agatha Christie's novels, the Star Wars movies, and Spiderman.