A Study in Magic
by Books of Change
Warning/Notes: This is a BBC Sherlock and Harry Potter crossover AU. The HP timeline and BBC Sherlock's timeline has been shifted forwards and backwards to match up. One major BBC Sherlock character's gender has changed for the sake of the plot. The story was planned and written before season 2 (but incorporating elements of thereof as much as possible). Readers beware!
Chapter Sixty One: Choices
Boxing Day morning, Severus went straight to the Headmaster's office after a meagre breakfast of toast and coffee. There he found Dumbledore sitting behind his desk and wearing a nightcap that had a ridiculous pompom dangling at the end.
"I see you've indulged in a bit of slumber," said Severus sardonically as he took a seat. "Perhaps you are getting on in years?"
"I have been since the day I was born," said Dumbledore as he stifled a yawn. "But never mind. There was something you wanted to tell me?"
Severus looked hard at Dumbledore with pursed lips. Then he looked up at the ceiling. It was far more difficult than he expected, the relaying of a vitally important piece of information he'd kept to himself for over a month…
Dumbledore remained silent while Severus composed himself.
"…It's coming back," he whispered, "The Dark Mark. Karkaroff's too— stronger and clearer than ever…"
"Ah," said Dumbledore quietly. "I was wondering when you would tell me this bit of information."
Severus snapped his eyes back to the headmaster.
"You knew?"
"I had a strong suspicion," Dumbledore sighed, "So how long has this been going on?"
Severus wondered if he should ask Dumbledore how long he'd suspected the Dark Mark's return. Then he decided it didn't matter.
"…I first mistook it for a stubborn bruise, but then it took a distinct form two days before the first task of the Tournament."
"And it has steadily grown clearer since?"
"Yes."
Dumbledore hummed thoughtfully. For a while neither of them spoke.
"I suppose you want to know what I know," said Dumbledore.
"I must," said Severus harshly. "The Dark Lord may return. Karkaroff plans to flee if the Mark burns."
"And are you tempted to join him?"
Severus froze for a second. He didn't expect the question, to be honest, but the answer for it he already had.
"…No," he said. "I am not such a coward."
"No," agreed Dumbledore. "You are a braver man by far than Igor Karkaroff. You know, I sometimes think we Sort too soon…"
Severus didn't want to hear more on this.
"So what do you know?" he asked brusquely.
"A great deal, and yet, not enough," Dumbledore replied after another sigh. "Now listen carefully, Severus. I do not wish you to be either misinformed or under-informed…"
Dumbledore then told Severus a lengthy summary: a wizard who once served in the Muggle armed forces and had worked for an infamous consulting criminal, the late Jim Moriarty, was now working for the Dark Lord, but he was not the main agent leading the efforts for his return; the agent was likely an old Death Eater, one who may have participated in an early resurrection attempt; the agent successfully infiltrated the ministry and the Triwizard tournament, and was attempting to kidnap Harry Potter (who else?) because the boy was somehow vital to the Dark Lord's return; the agent was using the Imperius Curse and the Polyjuice potion to replace one of the Ministry employees; various attempts had been made to uncover the agent, but so far the agent eluded capture …
"Why haven't you told me these things earlier?" Severus practically shouted when Dumbledore finished speaking.
"Oh, Severus, would you have listened?" said Dumbledore chidingly. "You have exploded at any and all mention of Sherlock Holmes these last three months, and he features in every point of the narrative."
"You're slavishly reliant on that man," snapped Severus. "Just because he was right a few times before doesn't mean he's right this time!"
"Is this an objection made without any prior commit to reject them?" asked Dumbledore, eyebrow raised.
"You presume that I'm fault-finding!" Severus snarled. "Perhaps I have reason to have a different list of suspects since I am, unlike Holmes, actually in the Magic World and have personal experience dealing with the Dark Lord!"
"Who do you suspect, then?" asked Dumbledore calmly.
"Rita Skeeter," Severus spat. "You've read her recent articles, have you not?"
"I have. What is it about them that rouse your suspicion?"
"You've banned the woman from entering Hogwarts, and yet she was able to access the school enough to write those florid articles on Potter," said Severus. "Some of the details were the sort that require personal eyewitness. Recall how she waxed eloquent on how well he plays the violin."
Skeeter had made good of her promise to write more on 'The Secret Life of Harry Potter' (Ha). As expected, one had to have a heart of stone to not laugh at the melodramatic reporting of Potter's tragic life (Ha, again). But once you disregarded the purple prose, the articles had startlingly accurate details on Potter's daily routine. Some of the facts one may possibly glean from the other students, but the details about his music lessons were something only Ms. Shin would know, and she would never divulge the information to a reporter, least of all Skeeter.
"Just because Ms. Skeeter had gained access to Hogwarts doesn't mean she is working for Lord Voldemort," said Dumbledore calmly. "After all, she is quite resourceful and tenacious where her reporting is concerned … and her usual modus operandi is working alone unless she needs a photographer."
"She may not know she's working for him," Severus argued. "She is determined to write about Potter, and as you've said, she is the type that will let not something trivial like a ban stop her. All the Dark Lord has to do is let her do what she wants, and use her access when the time is right."
"It's possible," said Dumbledore, nodding. "However, if Ms. Skeeter is the unwitting agent, how did Voldemort know to use her? Skeeter started making her mark as the kind of reporter she is now after he was vanquished. Where and from whom, then, could he have got the necessary information?"
Severus was momentarily stumped.
"…Bertha Jorkins," he said, rallying. "There is hardly any Ministry worker who doesn't know Skeeter's poison pen. Skeeter also reported her disappearance in August. The article said Jorkins left to visit her second cousin in Albania and never came back."
"And Albania is, incidentally, the last place Lord Voldemort is known to have been," said Dumbledore.
"Exactly. She could have met him or he could've found her; either way, as a ministry employee, Jorkins would've known about the Triwizard Tournament," said Severus. "It wouldn't have taken much to get her to talk, either. She was a pathological gossip when she was a student and I don't think she changed much since. No doubt the Dark Lord disposed of her once he gained all the information he could gain from her. Afterwards, it is only natural for the Dark Lord to check the news to see if the world at large noticed Bertha is missing. He would've learned Skeeter's name and reputation from the article."
"Again, very possible," said Dumbledore, smiling a little. "I thought of the possibility myself, so I relayed a few memories of Bertha as I remembered her as a student to Sherlock. He concluded after viewing them that she is the type to divulge the news of the Tournament easily. However, he and I are in agreement that this does NOT mean she was the one who told Voldemort about the tournament."
Severus frowned. "What do you mean?"
"Bertha, according to Bagman, has a memory like a leaky cauldron," Dumbledore explained. "This is not at all like the student I remember. She wasn't very prudent, perhaps, but there was nothing wrong with her memory. Exactly how is one to explain this change, I do not know, but it does strongly suggest we cannot draw inferences based on our old memory of Bertha. There is also a timing issue. Pettigrew escaped last year in December, with the help of an unknown assailant who attacked Bartemius Crouch. Bertha travelled to Albania this year in July. If indeed Lord Voldemort learned about the Triwizard Tournament through Bertha, why did he remain in Albania for so long? Could he not have travelled back to the UK long before that?"
"Why would he not stay?" Severus scoffed. "Pettigrew is a wanted man. Rather than travel with him—and he would have to—the Dark Lord may have chosen to lie low in Albania until the manhunt for Pettigrew cooled down."
"But would he wait for six months?" asked Dumbledore. "Also, Pettigrew wasn't the only person who would've sought Voldemort out. In fact, the unknown assailant was likely zealous to find him. Would not Voldemort rely on this person rather than Peter? He is far more loyal and the ministry still doesn't know who he or she is."
Severus was at lost to explain that.
"But this explanation is better than the one Holmes is expounding!" said Severus stubbornly. "The purported connection between the agent and Barty Crouch is based more on conjecture than reasoning! Does he even have a viable suspect? None of the players convicted of trying to revive the Dark Lord previously are capable to carrying out the scheme—the Lestranges are still in Azkaban and Barty Crouch, Jr., as you well know, is dead!"
"Sherlock and Harry acknowledge the difficulties," said Dumbledore calmly. "That's why they are perusing new and rather intriguing venue of evidence."
Severus was curious despite of himself. "And they are?"
"Have you," said Dumbledore, leaning towards his desk and moustache quivering, "heard of the term DNA?"
"No."
"It's a molecule that encodes the instructions on how a living organism work, form and function," said Dumbledore. "In simple laymen terms, our bodies know how to make blue eyes, black hair and so on because the instructions on how to make them are in the DNA. It is also the means by which we leave our unique traits to our descendants." The headmaster suddenly smiled as though in remembrance. "In the history of scientific discovery, it's a very recent one. I still remember the excitement over the discovery of the double helix structure of the DNA after James Watson and Francis Crick published their findings in 1953 … Such is the advantages of reading Muggle Newspapers."
"Interesting, but why exactly is DNA significant to our current case?" interrupted Severus.
"The DNA profile of each individual is unique," Dumbledore explained. "The exception is identical twins, but I doubt the agent is part of one, considering how old he or she is. Anyway, the Muggle Law Enforcement uses the DNA in blood, semen, saliva and hair found in crime scenes to identify a matching DNA of an individual, such as the perpetuator. Muggles also use DNA to establish the blood relationship between different individuals."
Severus started to vaguely see the significance of this.
"More likely than not, Lord Voldemort's current agent would have strong blood ties to some of the oldest wizarding families," Dumbledore continued. "The people who are directly related to these families are quite small in number, thanks to the tradition of pure-bloods marrying fellow pure-bloods to maintain the so-called purity of blood. Also, as the Headmaster of Hogwarts, I have intimate knowledge of the family structure of the last four generations of pure-bloods. Find which family the agent is most closely related to, and we can find who the agent is."
"But you need a sample of the agent's DNA in order to establish a blood tie," said Severus. "How are you to obtain that if you don't know who the agent is pretending to be? Also, didn't you say the agent may be using the Polyjuice potion? The potion turns you into a different person at the deepest physical level possible. Wouldn't the DNA change also?"
"I'm glad you asked me that!" said Dumbledore, his eyes twinkling. "To answer your first objection, you must realise who the agent would want to replace are few. Also, when and how long the agent can use the Polyjuice potion is limited to the amount of potion he or she can brew. There is also the question of where it is appropriate to use the potion."
Severus thought about it for a moment.
"You need at least a mouthful of Polyjuice every hour to maintain the transformation," he said. "That means you would need a cauldron's worth to stay transformed for a day. The ingredients are expensive and strictly regulated, the brewing period is a month long, and any contamination can result in hideous transformations that can take weeks to correct. Even if you correctly brew the potion, you need to accurately imitate the person you are replacing until it doesn't matter anymore. Thus, practically speaking, it's not a method one uses for an extended period of time."
"No. That's why Sherlock and I have concluded the agent is likely using the Imperius to maintain his or her cover on the day-to-day basis and is using the Polyjuice potion for operations that require a personal touch, namely the actual kidnapping of Harry."
"And you are certain the agent is merely trying to kidnap Potter, not do away with him."
"Yes," said Dumbledore firmly. "At the first task, the agent turned Harry's ministry-issued badge into a portkey. Fortunately, Harry removed the badge before it activated."
Severus felt cold. "So it's by pure dumb luck the plan was foiled."
"I wouldn't go that far," said Dumbledore. "There is a certain sense of hastiness bordering on carelessness in turning the badge into a portkey. After all, it's not that hard to imagine a badge hanging on one's neck to be cumbersome for someone flying on a broom. It is as though the agent was too zealous to get the task done. If I were to guess, I think the agent feels threatened by the military wizard who once worked for Jim Moriarty."
"That's pure speculation," Severus sneered. "Now I suppose you've collected multiple DNA samples of all the people who might have been replaced, in different settings and times."
"Yes," said Dumbledore. "I've also taken the liberty of obtaining hair samples of people closely related to known Death Eaters. Detective Chief Inspector Lestrade has incidentally told me he does not wish to ponder the depths of illegality of what we are doing."
"He is involved?" said Severus, frowning.
"Mr. Lestrade is very much aware his half-brothers Rodolphus and Rabastan will strongly object to his existence," said Dumbledore, "Then there is his functionally Muggle family to consider."
Severus tried to keep his face straight as he imagined Bellatrix Lestrange's reaction to learning about Mr. Lestrade. Oh, to be a bat on the ceiling when it happened…
"Thus he is eager to lend a helping hand," said Dumbledore, moustache quivering.
"Who else is aware of the situation?" asked Severus.
"Sirius and Remus, of course," Dumbledore answered. "There are also Mr. Lestrade's in-laws…"
Severus wet his lips as he remembered who Mr. Lestrade had for an in-law.
"So he's helping us this time?"
"He promised his full support."
"What brought the change of heart?"
"His heart has not changed," said Dumbledore solemnly. "He is, however, far more informed."
Severus frowned again. "I don't follow you."
"It may come to you as a surprise, Severus, but there was a time when old men such and he and I were young and, frankly, didn't know any better," said Dumbledore, smiling sadly. "June Hu also had the disadvantage of being foreign. I don't think wizards and witches born and raised in Europe and America understand how unusual our world is. June Hu lived without the concept of a separate magic world for most of his life. Even to this day his native country does not separate magic and muggle, and the magic people dwell among the 'ordinary' people."
Severus began to understand.
"Are you saying he didn't participate in the war against the Dark Lord because he wasn't part of the wizarding world back then?"
"Correct," said Dumbledore. "He knew we existed, and was rather surprised at our sheer numbers, but since the way we practiced magic was at odds with his way, he kept himself as hidden as possible to avoid conflict. We would've never heard of him, I am sure, if his wife was never kidnapped."
"1962," Severus breathed.
"The one and only," said Dumbledore softly. "I never had the privilege of meeting his first wife Huang Yue Ying, Severus, but all accounts point her to being a lively person who was eager to learn and make new friends. My guess is she astonished our kind with her unusual way of magic, and the news of her existence eventually reached Lord Voldemort." He paused. "The first time I met June Hu was after the incident. His first direct encounter with our kind being as it were, I was unsurprised when he declared he wanted nothing to do with us. I managed to keep an open channel by offering to teach him our way of magic, so that he would know what to expect from then on."
"So the distance education wasn't his idea, it was yours," said Severus. "I also thought he developed the magic removal curse when he worked at the Ministry. So it actually predates even his Hogwarts education?"
"Yes, for both questions," Dumbledore replied. "I learned after he finished his first year of independent study that he was hailed a prodigy in his motherland. Of course, by then, I could draw the inference without any assistance…"
Severus nodded slowly.
"I suppose he still had no good feelings for our world by the time he finished his education in wizardry and witchcraft."
"He cut all contact," confirmed Dumbledore. "He only started to slowly engage with our world when his daughters were born and later received Hogwarts letters. You know the rest."
Severus nodded again.
"What about my second objection?"
"I know one individual discovered an Animagus still retains his original human DNA even when he is in his animal state," said Dumbledore, his blue eyes twinkling again. "But the polyjuice potion may be different. We could test it, of course, but there are more parameters to consider. For example, we do not know what happens to the strand of hair that parted company with its owner's body. Even if the hair remains in its transformed state so long as the potion is still in effect, the profile is worthless if the owner's body returned to its original state while it was being generated. But it does not hurt to find out. We do have the luxury of time, since it is unlikely the agent will strike again until the Second Task."
Severus had a terrible feeling about this. "How exactly are you going to 'find out'?"
"Can you not imagine?"
Unfortunately, Severus could. "No. I refuse."
"Do you think a man like Sherlock Holmes would let your lack of cooperation stop him from discovering the truth?" asked Dumbledore mildly. "Also, think of what he would do as alternatives."
The alternative made Severus's blood run cold. "You're out of your mind if you allow it!" he bellowed.
"Regardless of my permission or how exactly Sherlock decides to perform the experiment, Harry will get involved," Dumbledore pointed out.
I hate you, Severus didn't say as he quietly fumed.
"You need to work with him, Severus," said Dumbledore solemnly. "Should the unthinkable happen, we will not be able to hide the fallout. Not this time. Not when almost every Muggle in the UK is equipped with a smartphone and camera that lets them record and post videos on the internet in matter of minutes. We need Muggle cooperation, and Sherlock Holmes is, strangely enough, the best person who can help us. Also, like it or not, he is Harry's father."
"So Holmes actually cares about him?" Severus spat. "I thought he didn't have the capacity to care."
"Caring is not his greatest strength," agreed Dumbledore. "But do you doubt he cares about John Watson?"
Severus went still.
"On that matter, do you doubt John cares about the boy?"
Severus continued to remain silent.
"Think carefully what John Watson would do before you make any decisions," said Dumbledore in conclusion.
-oo00oo-
Harry returned to Hogwarts the day before Christmas holidays were over. Hermione thought he looked quietly determined as he went around and greeted everyone except Ginny, who wasn't in the Gryffindor common room.
"Where is she?" Harry asked.
"She's, um, out seeing Michael Corner from Ravenclaw," said Hermione carefully, gauging his reaction.
Harry frowned and Ron looked startled.
"Why?" Ron blurted.
"He asked her out after the Yule Ball," Hermione answered. "She agreed to try it out."
Ron gaped like a stranded fish. Harry's frown increased. Hermione wasn't sure what the latter meant. Did Ginny seeing another boy bother him? If so why? Was it unconscious jealousy? Was she correct, after all?
Ever since Harry made it clear he had no thought to spare except for those dedicated to foiling You-Know-Who, Ginny confessed—very dejectedly—that she should stop harbouring the hope he'd notice her any time soon. Hermione agreed and told Ginny to get on with life, maybe go out with other boys so she could be more like herself. Julia agreed on the get on with life part, but didn't see why that meant Ginny should see other boys. Moreover, Julia argued, if the person Ginny ultimately wanted to be with was Harry, what was the point of seeing other boys? Hermione and Julia had a long argument over the issue. Then Michael Corner came along, Ginny made her choice, and that was that.
"…She decided to start seeing someone when we're not done with the case?" said Harry at length.
Hermione felt herself slumping. Of course Harry would stay single-minded.
"Don't worry, Harry, she's not the type to vanish just because she's seeing someone," Hermione sighed.
"But…"
"Oh, Harry, what's it to you if she is?" said Hermione testily. "You don't know if it's going to be too much of a distraction. Besides, she's free to see who she wants, it's not like you were seeing her, is it?"
Harry scowled.
"Fine, whatever," he said, turning away. "You update her later if you want to. I'm not doing it."
Hermione felt furious. "So you're going to cut her off just like that?"
"Who said anything about me cutting her off? I'm not the one absent," snapped Harry. "Now do you want to know the latest or should I just keep it all to myself?"
Hermione reluctantly dropped the issue.
The four of them quickly moved to the Music Room, where Julia was already waiting for them inside a drawn noise-cancelling screen. Harry seemed to notice the strange, awkward air between her and Ron, which had been hovering between the two since the Yule Ball, but didn't comment on it.
"I'll show you my memory of what Sherlock told me," Harry started as he dug out his memory harvesting charm from out from his inner jacket pocket. "Maybe it is best Ginny isn't here. We can't tell her anything about the memory harvesting spell, after all. Oh, and before we watch, you should have this."
Harry handed out to everyone a paper charm. All of them had elabourate Chinese calligraphy written in rusty-brown ink. Hermione suppressed a shiver as she wondered if they were all written in blood.
"What is this?" asked Ron.
"Something that stops people from eavesdropping into your brain," Harry explained. "It's just a precaution," he added when Neville and Ron sputtered. "Not many wizards and witches are capable of doing it, and eye-contact is crucial in order to do it, but you never know."
Once everyone got a paper charm that blocked mind-intrusion, Harry placed his memory harvesting paper charm on his phone. Immediately the holographic image of Sherlock sitting on a leather-upholstered chair with his knees drawn to his chest and his hands clasped together under his chin projected out of from the phone.
"…You recall there is evidence that the agent was present at the First Task, but the map appeared not to reveal his name," said the holographic Sherlock. "That in itself is an important clue."
"How?" said Hermione, Ron and Neville all at once, though there was no way the holographic Sherlock could hear them.
"How can you have the appearance of a different person, and avoid the detection a map that reveals your true name?" Sherlock went on.
All three drew a blank for several seconds. Harry looked at them with a grim smile on his lips.
"Replace a person who has the same name as you," he answered in sync with the memory-Sherlock.
Hermione's eyes went wide.
"Oh, oooh…!" she stuttered, as everything slowly came together, but then not quite.
"Remember," Sherlock intoned, "that four people were convicted of trying to resurrect LV shortly after his fall: The Lestrange brothers, the elder Lestrange's wife, and Bartemius Crouch's son. This son, incidentally, shares the same name as his father: Bartemius Crouch, Jr."
Now Julia, Ron and Neville's jaws were hanging open.
"And … and Barty Crouch is one of the people we think the agent replaced!" Neville squeaked.
"He also sacked Winky!" said Ron in rush. "What if … what if the second person in his house at Christmas was his son? What if it was Winky's job to take care of his son and keep him hidden? What if this son was right there to listen when Grandmaster Shin told Crouch about Pettigrew?"
"Then of course Crouch would sack her," said Julia breathlessly. "She failed to do her job."
"But … why would the son be in his house?" sputtered Hermione. "He's supposed to be dead! How did he escape from Azkaban? He wasn't an animagus, was he?"
"Sirius said Crouch and his wife were allowed a deathbed visit," said Sherlock. "Dementors are blind. They sensed one healthy person and one sickly person entering, and one healthy person and one sickly person leaving. Of the three players of the visit, two of them were sickly to the point of death. So who is to say which of the two had actually left? Also, would it surprise you if a deeply loving mother decided to switch places with her son, and was careful to take a potion that lets her assume the appearance of said son to the day she died?"
The five of them were speechless.
"But this is just a theory," said Sherlock, turning very serious. "There are certainly a lot of strongly suggestive clues that support it: Besides all that we know so far, Ellen has told me that she overhead Winky teaching Treble that a House-elf must always keep her master's secrets. Ellen had the foresight to ask her further questions about it, and Winky confirmed that she had been entrusted with her master's deepest secret, singular, which of course she cannot reveal. That this secret is Crouch smuggling his son out of prison is an attractive idea, but it is not a necessary inference. Crouch doesn't seem the type to do such extra-judicial acts, even for the sake of his dying wife, but one never knows. In short, we still do not have clinching evidence."
The five of them nodded.
"So we are back where I've left you," said Sherlock, looking stern. "We must find out if the polyjuice potion changes a person's DNA profile after consumption. If it turns out it does not, then we will collect a sample of whoever shows up as 'Bartemius Crouch' on the map during the second task — and by 'we' I don't mean you, Harry. No, don't give me that look. The agent is tasked to kidnap you, so you approaching him would be the height of stupidity. Leave the task to Dumbledore. If it turns out the potion does change your DNA profile, then we will exhume the body buried as Barty Crouch, Jr. Either way, believe you me, if you try to approach the agent, I will have your hide."
Harry turned off his phone.
"That was Sherlock's Christmas present for me," Harry said. "Usually he keeps the solution to himself to the very end, and he didn't have to tell me all this, but… "
"He told you anyway since you needed to know," said Hermione quietly.
"Yeah," said Harry, blinking rapidly. "Anyway, the polyjuice potion—John vetoed us brewing it on our own. I mean, what if the potion gets contaminated and we drink it without knowing?"
"I can see that," said Julia "Like, if a fly drowns in the potion, we might turn into a fly abomination."
"Exactly," said Harry while Neville, Ron and Hermione winced, "So no brewing the potion without supervision."
"But who's going to supervise?" said Ron. "I don't fancy asking Snape."
"There's Professor Moody," said Hermione.
"Do you really want to ask him? He might jinx us all and then tow us to the Magical Law Enforcement just to make sure we're not up to something. Remember what he said he did to the witch who said 'Boo' behind his back."
"Sherlock already arranged everything," said Harry. "He should be here now. Let's go."
They left the screen.
Everyone was struck silent as they caught sight of a very familiar looking man wearing the shiniest suit Hermione had ever laid her eyes on—it was if he'd made it with aluminium foil. He was also wearing a white-and-purple diamond patterned shirt and a horrible tie that looked like the Atlantic Ocean had mated with bright orange fabric.
"Everyone, meet Dr. Robert Dongyi Ju," said Harry. "He's a genius healer. He's also a bit mad."
"Only a bit, that was nice of you," said the man, grinning goofily and waving. "Hi, I'm Robert."
Hermione considered running away, and saw corresponding emotions on Ron and Neville. Julia just covered her face behind a hand.
"Of course it's you."
-oo00oo-
Final Notes: Snape returns! I missed writing from his POV. ASIM!GOF is at its last stretch, readers!
I wrote down this long philosophical dialogue for Sherlock on whether DNA would stay even after Animagus transformation or polyjuice, but then Harry reacted with "You lost me completely," so I scraped it. Maybe later.