Author Note: This is my first attempt at fanfiction, and I am so excited that it is finally posted. This is based off one of my favorite Sherlock Holmes stories, and I hope you all enjoy it.

Disclaimer: I do not own Sherlock Holmes in any way, shape, or fashion.

May 19th, 2013: I made a few minuscule adjustments to word choice and deleted a repeated revelation concerning Savage's cousin, Margaret.

John Watson was dying.

Sherlock Holmes sat in an uncomfortable chair staring at his friend's still form. John, not a tall man by any means, looked even smaller lying in the hospital bed, hooked to a ventilator that controlled the rise and fall of his chest, insuring that the heart rate monitor kept up its steady beat. Before the end, the nurses told him, they would most likely need to put John on Extracorporeal Membrane Oxygenation, where a machine would oxygenate his blood, a job his heart and lungs would normally perform if the Hantavirus coursing through John's body hadn't started destroying those organs.

Sherlock felt the panic start to well up in him again; it was such an unnatural occurrence for him that the rational part of his brain managed a twinge of surprise every time he experienced the gut-freezing sensation. The end of John Watson. The thought sickened Sherlock. Especially because he had played a part in bringing about the demise of the one person who had been able to put up with his aggravating genius and then go one step further by befriending him. And now John would never again race through the streets of London with Sherlock or roll his eyes at Sherlock's inability to go grocery shopping or help stave off Sherlock's boredom by arguing with him.

This nightmare had all started 6 days, 1 hour, and 43 minutes ago…

John came back one day from healing London's sick and weary complaining of aches throughout his body, but especially in his shoulders and back. Sherlock just assumed John's war wound was acting up again. The London weather had been unusually damp as of late. But he started worrying a bit when John made to get up from the couch but quickly sat down again after seemingly experiencing a spell of dizziness. He waved off Sherlock's concerned look.

"It's probably just the bug that's been going around. We've seen a lot of patients with flu-like symptoms lately," John said. "I think I'll just stay on the couch for now." Sherlock just shrugged and turned back to the electron microscope images Molly had sent him that afternoon.

Something about the death of Victor Savage seemed wrong to him. That an accountant could contact a deadly disease usually transferred by lab rats and die a week later seemed a little too convenient. He had gotten Molly to send him the images and was looking for anything out of the ordinary. John fell asleep on the couch without even attempting to figure out what Sherlock was working on, which sent another twinge of concern through Sherlock's mind.

Sherlock pulled a blanket over his friend before heading up to his room to muse awhile in his mind palace. Savage's blood contained only the one pathogen as the report had stated, but it looked different from the textbook Hantavirus depicted in the stock image from the lab. How had it gotten into his bloodstream in the first place? They were releasing the body to Molly tomorrow. He would have to go sweet-talk her into giving him a look at the corpse.

The next day Sherlock woke early to find John still passed out on the couch. He left John a short note, "Going out," and then headed to the morgue at St. Barts. Molly was waiting for him at the door, clothed in a protective suit, and holding a matching one up for Sherlock. "I figured you would want to have a look," she said in the slightly stammering tone of voice she always used around Sherlock. Sherlock gave her a small, but genuine smile as he reluctantly took the suit from her.

"Excellent, Molly. That was quite thoughtful," Sherlock said only half-faking the appreciative tone. Molly shot him an incredulous look.

"Right then," she said hesitantly. "I'll leave you to it." She started to leave the room then turned around. "Where's John?"

"He's feeling a bit under the weather," Sherlock replied, already losing interest in the conversation now that he had a body to focus on.

"I hope he feels better," Molly offered.

"I'll relay your sentiments," he said quietly, though in reality he had barely registered her comment. Sherlock heard the door shut as Molly left the room and he sighed with relief. Now he could work his magic.

Victor Savage. 32 years old. High level of physical fitness judging from his toned muscles and the calluses on the sides of his big toes. Most likely an avid runner with shoes that were slightly too narrow in the toe. Dark tan, but no signs of the tan line left by a ring, thus unmarried. Ear pierced many years ago, but he had let the hole close up. Teeth stained red. That would suggest bleeding from the gums or throwing up blood. Slight blackening at the fingertips most likely caused by gangrene. A pinprick on his waist: site of injection.

He looked at the hospital chart Molly had left behind. Savage was not diabetic nor did he have any other preexisting health conditions that would explain the needle mark. So what could have caused it? Savage had not know he was dying, so the murderer probably hadn't drugged him directly. An indirect injection then. Maybe a needle concealed in a device of some sort. The injection had been shallow, but had left a large mark. They were looking for a short, but thick needle.

Sherlock stepped away from the body and frowned. Something here wasn't quite right. Hantavirus did not usually cause bleeding gums or lead to gangrenous fingers. He sent Molly a quick text, "Come to the morgue. Need your opinion."

Molly walked in a few minutes later and stood next to Sherlock. "What do you make of this?" he asked, showing her the fingertips and red-stained teeth.

Molly leaned in a bit closer to examine Savage's body. "Don't know. Those symptoms aren't typical of Hantavirus, though. But there was only one pathogen in his blood," she said, puzzled.

Sherlock didn't answer. Something about this case seemed vaguely familiar, but he could not seem to turn the nagging suspicion into anything concrete. "See if you can get another analysis of the pathogen," Sherlock said.

"Oh, okay," Molly stammered. "I'll get right on that." Sherlock started for the door, but stopped as he opened it. "Thank you," he said stiffly, and then walked out. Molly stared at the now-closed door in amazement. John Watson was having a profound effect on Sherlock Holmes; anyone who said otherwise was a fool.

Sherlock walked briskly into Lestrade's office. Lestrade, as usual, looked less than pleased to see him. "What do you want?" he asked brusquely. "And where's John?"

"Why is everyone so concerned by John's absence? He's caught some sort of bug from work," Sherlock said dismissively.

"We're concerned because it's a rare sight to see one of you without the other, but especially to see you without him. Tell him I'm sorry he's sick by the way," Lestrade said standing up from his desk and stretching.

"I'm sure your condolences will noticeably lessen his suffering," Sherlock said dryly. He did not understand the point of all these useless social niceties. Why would John care if people were sorry he was sick? It wouldn't make him feel any better.

Lestrade ignored this and reworded his earlier question, "Sherlock, why are you here?"

"I need to look at Victor Savage's belongings," Sherlock answered.

"The man died of a disease. It's not a homicide," Lestrade sighed exasperatedly, praying that Savage had met his end by natural means. He did not need another case right now.

"I'm not saying he didn't, but his death was anything but natural," Sherlock responded as if reading Lestrade's mind. "What were his final words again? Did he or did he not gasp to the paramedics with his dying breath, 'He's done me in?' " Sherlock asked icily. "There is a high probability he was murdered, but his murderer was crafty enough to make it look natural." Lestrade treated him much more cordially when John was around. Sherlock filed that away in his mind for future contemplation.

Lestrade pinched the bridge of his nose. "Yes, but we figured he was just delusional. The man was working with an oxygen-starved brain," Lestrade reasoned.

"And yet Hantavirus does not cause hallucinations or madness," Sherlock replied. "The data suggests Savage was murdered. I found a needle mark on his waist. He wasn't a diabetic and had no preexisting conditions or recent health problems that would explain such a mark." Lestrade sighed.

"Right then. Let me go find his things. But I can't take you to his place until tomorrow. The team has to disinfect it first. They don't mess around when it comes to disease. And no, that does not mean you can go by yourself." Sherlock smirked despite himself. Lestrade knew him far too well. The Detective Inspector came back a few minutes later with Savage's personal effects.

"These had to be disinfected as well, so we can't get any prints from them. All he had on him was his wallet and cell phone. The paramedics found him on the floor of his flat after he called. He died en route to the hospital," Lestrade stated. "One of his mates who ran with him said he had called off their morning run for the past week because he wasn't feeling well."

Sherlock opened Savage's wallet. A gym membership, a few credit cards, and an identification card, along with a few crumpled bills and some loose change made up the entire contents of the wallet. No hidden needles, but he hadn't really expected there to be. The mark had been too high up on his body to be from something in his pocket.

Sherlock handled Savage's cell phone with more caution, but again he found no needle or any sort of hidden compartment that could have contained one. This phone was old. A model from a few years ago; the scratches covering its surface showed it had been well used. Whatever had contained the needle that introduced the virus into Savage's bloodstream would have to be new. Hopefully, the flat would have more answers.

Sherlock seriously debated heading over to the address without Lestrade (he had looked it up on the computer while Lestrade was busy locating Savage's possessions), but he didn't want to start a feud with the Detective Inspector. With John temporarily out of commission, he needed to stay on Lestrade's good side. Maybe Lestrade would give him the address for the firm where Savage worked. A quick text message later, and Sherlock had what he needed. Sherlock flagged down a taxi and gave the cabbie his destination.

Sherlock walked through the door of 221B several hours later, carrying a bag full of deli sandwiches and soup. "John," he called. "I've brought dinner." Secretly, Sherlock was quite pleased with himself. He relished the surprised and grateful look on John's face whenever Sherlock did something nice for him, even though he would never have admitted it to the doctor.

"What's the occasion?" John asked sarcastically from behind Sherlock. The detective turned with a retort on his lips, but it died in his throat as he caught sight of his friend. John looked terrible. He had a comforter wrapped around his shoulders, but Sherlock could see the shivers that wracked his body. His skin had turned a sickly shade of grey and dark circles marked the skin under his eyes. John had managed to catch a nasty case of the flu.

"You look ghastly," Sherlock observed.

"Well, we can't all have cheekbones like yours," John said with a small smirk. Sherlock gave him one in return. At least John still had his sense of humor. Sherlock frowned at the flicker of pain that shot across John's face as he lowered himself into a chair.

"You should see a doctor," Sherlock observed.

"I am a doctor," John snapped back.

"Undeniable proof that doctors make the worst patients," Sherlock muttered. John smiled a bit at that.

"If it doesn't clear up by the end of the week, I'll go," John conceded. Sherlock nodded in satisfaction.

"Molly and Lestrade send you their condolences," he offered.

"That was nice of them," John replied. "So, how is the Savage case coming along?"

Sherlock filled John in on the day's findings. He then went on to recount what he had learned from Savage's secretary. "It seems the Savage family has been plagued with misfortune death. His uncle was diagnosed with terminal cancer a year ago, and he took a turn for the worse right before Savage's murder. Savage's parents died when he was young and this uncle, Fitzwilliam Smith, adopted him, as he had no children of his own. He's been out of work for a week, claiming a bout of the flu."

"Only to die a few days later. Poor man," John said shivering again. "Right, well you're on the trail now, so he'll be avenged. Back to the couch for me. Thanks for the soup."

"I'll put the leftovers in the fridge," Sherlock responded, but his keen eyes had not failed to notice that John had barely eaten a dozen spoonfuls.

"Just keep them well away from those pickled toes you have on the middle shelf," John warned. "I don't want to find one of those in my bowl tomorrow."

The next day John had not improved, but he hadn't worsened either. As Sherlock was heading out the door to go with Lestrade to the flat, John commented, "You know, this case seems familiar somehow." Sherlock turned back to his friend.

"I thought the same thing," he replied. "But why?"

"Don't know," John answered. "But I'll try to figure it out while you're off solving crimes without me." Sherlock gave John a small smile and then left his friend to recover and watch crap telly.

Savage had lived in a small, but neat flat. Tidiness must come as part of an accountant's nature, Sherlock thought wryly.

"So, what are we looking for then?" Lestrade asked as he stepped into the kitchen followed by a team decked out in biohazard suits. Sherlock had reluctantly agreed to wear one as well. Apparently, one couldn't be too careful when it came to Hantavirus.

"Anything that could contain a needle," Sherlock said, his voice slightly muffled by the suit. "A needle 2 cm in length and 0.6 mm in diameter, so thicker and shorter than a standard hypodermic needle." Lestrade and the rest of the team began to spread out across the flat.

"Call me over if you find something that could hold a needle of that size," Sherlock shouted. "Do not touch or pick it up, as the mechanism could still be engaged."

Sherlock left the bedroom to the rest of the team. A pile of letters lying neatly in a letter holder on the kitchen table caught his attention. A return address for a law office decorated the corner of each envelope. He pulled out the most recent letter entitled, "The Last Will and Testament of Fitzwilliam Smith." Sherlock quickly read through the will. His mouth turned up into a slight grin.

Smith had left everything he owned to his nephew, Victor. This added up to a far from trifling sum. Sherlock turned as Lestrade shouted his name from Savage's bedroom. Sherlock walked up to Lestrade and the team who were gathered around Savage's bedside table. He handed the will to Lestrade.

"Now our killer has a motive," Sherlock stated as he knelt down to look at the high-tech pedometer sitting next to the alarm clock. "This is the murder weapon. As soon as Savage attached it to his trousers, he activated the spring mechanism hooked to the clip. The question is, why didn't he get suspicious when his pedometer stabbed him?"

"We also found this in a box in his trash," Lestrade said handing Sherlock an instruction manual. "It supposedly monitored vital signs by occasionally taking a blood sample."

"Ingenious," Sherlock murmured. "Though a smarter man than Savage would have seen through that in an instant."

"The box was from his uncle, Fitzwilliam Smith," Lestrade added.

"That can't be right. Why would the uncle want to kill the nephew he named heir in his will? We need to talk to Smith," Sherlock said.

"The man's dying, Sherlock," Lestrade let out exasperatedly. "We can't just phone him up."

"Was there a letter from his uncle in the box?" Sherlock asked.

"There was actually. Only a short note," Lestrade replied, confused at the sudden change of subject. He handed the slip of paper to Sherlock who quickly skimmed it.

"Just as I thought. Our killer has slipped up. Compare this signature to the one in the will. They look nothing alike. The W in the will is sharp, while in the note it's rounded. The dots on the Is in the will are circular, while those in the note are more like dashes, and the difference between the capital Fs is so pronounced even a child would notice it. And don't even bother to suggest his handwriting has changed as a result of his worsening illness as the package and will are both dated after his condition worsened," Sherlock rattled off triumphantly.

Lestrade quickly closed his mouth, as he had been about to suggest the differences might have been the result of illness.

A phone vibration interrupted the silence following Sherlock's announcement. "It's from John," Sherlock said, frowning slightly. He didn't understand why a text from a sick John would make his gut twist with a split second of worry; sentiment was so irrational.

Margaret Beecher died of Hantavirus. Started looking into her case 6 months ago. Put it on hold when we got involved in the Affair of the Opera House.

Sherlock rolled his eyes at the dramatic title John had given to their most recent high-profile case. A serial killer had been murdering actors playing Joseph Buquet in showings of The Phantom of the Opera all over the country. He responded simply to John's text, Well done –SH, and then turned to Lestrade.

"We need to find out if Victor Savage had any connection to Margaret Beecher. She also died of Hantavirus, which aroused my suspicions six months ago. John and I started looking into it, but then we had to tackle the 'Affair of the Opera House,' as John has decided to name the case concerning the Joseph Buquet serial killer."

"That was a good one," piped up one of Lestrade's team. "Dr. Watson really has a way with the words for a medical man." Sherlock ignored him, his mind already running over all the data he had collected for the Margaret Beecher case. Margaret had been 35 and married with two children. She was an avid tennis player. It had taken her only 3 days to succumb to the disease, most likely due to complications from asthma. She had worked as an environmental consultant for a firm in London and did not have any known contact with lab rats.

"I need to talk to Margaret Beecher's husband," Sherlock stated to the room at large. "We need to find whatever device introduced Hantavirus into her system."

Lestrade nodded while listening to whoever was on the other end of his phone. "Right," he said as he finished the call. "Turns out Beecher and Savage were cousins. I've got the address for Beecher's husband."

Sherlock followed Lestrade to the door and then turned to give the rest of Lestrade's team one last order, "Get that needle analyzed for traces of Hantavirus and dust it for any fingerprints not belonging to the victim."

"Do as he says," Lestrade ordered without even turning around or slowing his pace. God help him if he was going to let Sherlock Holmes have the final word with his team.

The Beechers lived in a small house outside of London. A girl, aged about 7 years, answered the door. "Is your father home?" Lestrade asked in the tone adults reserved for children. "We need to ask him some questions." The girl nodded, gestured for them to come into the house, and went off in search of her father. Seconds later, a black-haired man—whose body posture and doleful expression showed that his wife's death still haunted him—came to the door, a puzzled expression on his face.

"Who are you and what are you doing in my house?" he asked defensively.

"No need to be alarmed," Lestrade said, flashing his badge at Mr. Beecher. "I'm Detective Inspector Greg Lestrade. I hate to make you revisit such a painful topic, Mr. Beecher, but we need to talk to you about your wife's death."

"Murder, actually," Sherlock corrected. Mr. Beecher stared at them in horror.

"My wife died of a terrible disease. She wasn't murdered. Who is he anyway?" Mr. Beecher asked angrily, gesturing at the consulting detective.

"Sherlock Holmes. And yes, your wife was murdered," Sherlock replied.

"I've seen your name in the papers. You're the one looking into Victor's death. He and Margaret were so fond of each other," Mr. Beecher replied, most of the anger leaving his eyes as he mentioned his dead wife.

"Mr. Beecher," Lestrade said with compassion in his voice, trying to make up for Sherlock's lackluster social abilities. "We have good reason to believe the man who killed Victor Savage also murdered your wife. Can you think of any reason why someone would want to kill Margaret?"

Mr. Beecher rubbed his eyes and sat down in a chair in the living room, gesturing for Sherlock and Lestrade to make themselves comfortable. "No. Margaret didn't have any enemies or even any petty rivalries. She was one of those people who could get along with anyone," he said.

"Did anything out of the ordinary happen before she died?" Lestrade questioned. "Did she receive any strange news or packages?" Mr. Beecher sat in thoughtful silence for a moment.

"There were two things actually. Victor had just named Margaret the executor of his estate in the case of his death. We thought he was a bit young to be writing a will, but he was always a man who liked to be prepared. As of this will, Margaret would also inherit all his money and possessions if he passed away."

"Meaning she would have also inherited her uncle's estate from Victor in the case of her uncle's death," Sherlock mused aloud. "What was the second thing?"

"She received a package from her uncle about a week before she died," Mr. Beecher said.

"Let me guess," Sherlock said, standing up to pace in front of the couch. "It contained a high-end pedometer that monitored vital signs by taking blood samples?" Mr. Beecher gaped up at the detective.

"Yes, but how could you know that?" he asked in amazement.

"Because Victor Savage was murdered using the same method. The pedometer's clip activated a spring mechanism connected to a needle coated in Hantavirus," Sherlock explained.

"But why would her uncle want to kill her? They weren't as close as he and Victor, but they got along extremely well," Mr. Beecher explained.

"Because her uncle didn't send it," Sherlock said exasperatedly. John would be shooting him a look if he were here, reminding Sherlock to play nice. "His signature was a forgery. Has anyone touched the pedometer since?"

"No," Mr. Beecher replied. "I still haven't been able to bring myself to clean up her stuff. I know it's been six months, but I still can't wrap my head around the fact she's never coming back." His eyes began to get a bit misty. Sherlock hated this part; he was no good at offering words of comfort. John always handled any consoling that popped up on a case. Luckily, Lestrade stepped in at that moment.

"I'd like to say it gets easier, but that would be lying. The pain just shows how important your wife was to you, so cut yourself a bit of slack," the Detective Inspector said, shooting the man across from him a look of sympathy.

"Do you mind if we inspect her belongings?" Sherlock asked. Lestrade groaned inwardly. The consulting detective had the emotional timing of a rock. Mr. Beecher took a deep breath, composing himself.

"Of course not. Our bedroom is just upstairs," Mr. Beecher said, leading the way out of the sitting area. The bedroom did not seem to know one of its occupants had died, as a variety of female possessions were littered throughout the room. Perfume and make-up dominated one side of the bureau. A paperback historical romance novel sat on the left bedside table, a mint green bookmark sticking out about three-quarters of the way through. Jewelry glittered from various resting places around the room. But the pedometer was nowhere in sight.

"Do you know what she did with the pedometer?" Lestrade asked.

"Unfortunately, no. I haven't seen it since…since she died," Beecher replied, tapering off at the end of the sentence. Sherlock sighed. Really, this man was no help at all.

"Did your wife say anything strange before she died?" Sherlock asked.

"Now that you mention it, she did actually. I was at the zoo with the kids for the day and I came home to find her…dying. She could barely breathe, but she kept trying to gasp something out. Her last words to me were, 'He…killed…me,' and then she was gone. The most amazing woman I will ever know. If you'll excuse me a moment," Beecher said, leaving the room.

So, Margaret Beecher had also known the identity of her killer. If the pedometer was not in plain sight, then perhaps she had been clever enough to hide it to keep it from falling into the hands of her children. But where? Where would a dying woman have put it? Someplace her husband and children would never look. Of course, how painfully obvious.

"Mr. Beecher," Sherlock called, striding from the room. "That door leads to your wife's office, I presume?"

"Yes, but what does that have to do with her case? She died in the bedroom," he answered.

"But she hid the murder weapon somewhere you wouldn't find it. Perhaps, in a safe in her study," Sherlock said, walking into the office only to have his words vindicated. Sherlock crossed the room to the safe in two quick strides, opening the safe as if he had come up with the combination.

"How did you know the code?" Beecher asked, startled. "She didn't even tell it to me."

"Your wedding day. Your wife loved you very much, Mr. Beecher, or else a bright woman like her would have chosen a much more intricate combination. Bag, Lestrade," Sherlock said brusquely.

"Hold on, Sherlock. I've got to call in the team. Some things have to be done by the book," Lestrade said, pulling out his phone. Sherlock breathed in sharply through his nose. Such tedious rules, but Lestrade's tone suggested he would not back down, and John wouldn't have wanted him risking his life just to prove his cleverness.

The detective wandered back into the Beecher's room. Lestrade and Beecher had not noticed the word, "study," highlighted in a clinical research report Margaret had placed on the table next to her unfinished novel. Sherlock would have looked in her office first anyway, but he appreciated the woman's intelligence. A woman that smart would have left some kind of clue about her murderer (hoping someone more observant than her husband would notice), assuming she had had time before she died.

Sherlock's eyes roved about the room, but kept being drawn to the jewelry strewn across the dresser. From a distance, the pieces looked as if they had been tossed about randomly, but when Sherlock stood above them and looked down, he could clearly make out the letters UCS. Sherlock smiled. The murderer had made a mistake when he decided to mess with Margaret Beecher. "Lestrade," Sherlock called, and the Detective Inspector came running into the room, followed by Beecher. "Look at this."

Lestrade swore under his breath and turned on Beecher. "Did you ever notice this before?"

"Notice what?" Beecher asked, squinting at the jewelry. Sherlock rolled his eyes.

"Your wife left two clues behind before she died. First, she highlighted the word study on this scientific article from work, leading me to conclude she had hidden the murder weapon in her study. Second, she arranged her jewelry into the letters UCS, most likely giving us the initials of her murderer. It's a good thing you didn't touch anything or we would have had nothing to go on," Sherlock stated with a hint of annoyance in his voice.

Beecher just stared at Sherlock who had started to pace the room, eyes closed. Lestrade grabbed the man's arm and led him into the hallway. He knew by now how to tell when Sherlock would find other people thinking in the room an annoyance.

Three letters. UCS: University College School. University Campus Suffolk. Universal Character Set. None of those made sense. Think! It had to be a name; the woman had been dying, and that would be the most obvious clue to leave. Urban Charles Savage. Ulysses Christopher Smith. Too many possibilities. He needed more to go on than this. Sherlock heard the team arriving downstairs and then Lestrade burst into the room.

"Fitzwilliam Smith died this morning," he announced.

"Who will inherit the estate?" Sherlock asked.

"The weird thing is, they don't know yet," Lestrade explained. "Victor's dead, and so is Margaret, so the money should go to the next blood-related male in the family. Strange thing is, all of Smith's brothers are dead."

"Not all of them," Beecher spoke up from the doorway. "That was the story they told, but I remember Margaret told me a story about one of her uncles. He fought with the rest of his brothers and got himself all-but-legally removed from the family. Margaret had a picture of her dad and the rest of his brothers as kids somewhere."

Beecher rifled through one of the drawers of the bureau, finally pulling out a sepia-colored photograph of four boys linking arms. He turned the photograph over and pointed out Margaret and Victor's fathers' names. And there, next to the name Fitzwilliam Smith was the name Frederick Culverton-Smith.

Sherlock let out a sigh of realization and frustration that he had not seen it sooner. "Of course," he breathed. "U stands for uncle. UCS is Uncle Culverton-Smith. It all makes so much sense. Culverton-Smith was kicked out of the family, but since it wasn't a legal disownment, he could still inherit the estate. When he found out brother dearest was on death's door, he eliminated the two threats between him and a wealthy future."

"That's all well and good," Lestrade countered. "But we don't have any proof."

"Not yet," Sherlock replied, the fire of the chase burning in his yes. "Thank you, Mr. Beecher for providing us with such a vital piece of information. Come, Lestrade. We need to discover the truth about the fourth Smith brother."

Hours later, the clock in Lestrade's office read 7:00 p.m. They now had the full biography of Culverton-Smith. He was a medical researcher specializing in diseases transmitted by rats. He had been fired from the company 10 years ago when they discovered that he had secretly been studying Hantavirus by purposefully injecting rats with the virus. His brothers, ashamed and alarmed at this development, had quarreled with Culverton-Smith and cast him out of the family. Smith had left the country, and his current whereabouts were unknown. The last anyone had seen of him, he had been living in Thailand, but that had been 4 years ago. He had no address in London, nor any Internet or credit record, and there had been no activity on his bank account, as the bank reported that he had taken his life savings with him when he left England.

Culverton-Smith had all the makings of a man who would murder his nephew and niece, as well as access to, and knowledge of, the disease that had killed them. Unfortunately, they currently had no way of locating him, nor any definite proof linking him to the murders. Forensics had only found the victims' prints on the pedometers, and despite Anderson's colossal idiocy, even he couldn't botch a simple fingerprint analysis. The only positive in all this was that the needles hidden in the pedometer had been coated with Hantavirus. Other than that, they had reached a dead end.

Sherlock growled in annoyance. "There has to be some way to fish him out! Some way to get him out of hiding and wring a confession out of him."

"There is," Lestrade said slowly. Sherlock turned to look at him, confusion written on his face.

"How?"

"Fitzwilliam Smith was a bit old-fashioned. He had a line in his will that the heir would have to receive the money in person within a week of his death or all the money would go to charity, and the house would become a nursing home. So, Culverton-Smith has to come crawling out of his hole like that rat that he is in order to see a single pound of the inheritance," Lestrade said beaming.

Sherlock blinked slowly. For once, the Detective Inspector had stunned him into silence. Sherlock was saved from complimenting Lestrade by his phone vibrating. He briefly registered John's number on the screen, only to be met by Mrs. Hudson's frantic voice.

"Sherlock," his landlady said, fear in every syllable. "You need to come home now. John's not well. He can barely breathe, and he keeps gasping out something about a magnifying glass. I called an ambulance. Oh, please hurry, Sherlock, "

Sherlock barely registered the phone slipping out of his hands or Mrs. Hudson's sob-filled voice asking if he was still there. He felt a strange numbness taking hold of his body. The never-ceasing gears of his mind had suddenly stopped working, and he was overly aware of his own breathing.

John and his infernal crusade to bring tidiness to their flat. The magnifying glass he had gotten in the mail a week ago. The one he hadn't touched because he had seen the spring mechanism hidden in the handle. A mechanism that had probably triggered a needle coated in death, just like the pedometers. And John had picked it up because Sherlock couldn't afford the 2 seconds it would have taken to dispose of it properly or even the 20 seconds it would have taken to warn John not to touch it.

John would die. This wasn't something Sherlock could solve; cleverness didn't matter when it came to disease. The loyal doctor had unwittingly taken the "bullet" meant for Sherlock. John would die, and Sherlock would be alone, but it would be worse now, now that he knew what it meant to have a friend. He let out a strangled sob, but his eyes mercifully remained dry.

Sherlock looked up from the ground as Lestrade put his hand on the detective's shoulder. He handed the phone back to Sherlock who numbly put the device in his pocket.

"The paramedics have arrived, and they've taken him to Barts. They think he was just having a fit, so he's not in any immediate danger," Lestrade said, visibly shaken. When Sherlock didn't respond, Lestrade put his hands on Sherlock's shoulders and gently shook him. "Sherlock. He's not dead yet."

"No," Sherlock said softly. "But that doesn't mean he won't die."

I apologize for leaving off on a semi-cliffhanger, but I have to keep your interest somehow. I meant for this to be a one-shot, but Sherlock and John decided to lead me on a longer journey. Thanks for reading and reviews are welcome.