"Murder case. Just celebrating its twelfth birthday."

"Mm," Sherlock said with feigned disinterest, tapping his index finger absently against his lips.

"Locked room in an art gallery in Mayfair," Lestrade continue. "One of Donovan's first big cases, actually."

At this, Sherlock deigned to look up, arching an eyebrow curiously. He stayed silent and Lestrade sighed.

"The victim, Patrick Connolly, was found dead in a locked office only three gallery staff and the cleaning woman had access to. The coroner put the time of death around midnight but Connolly wasn't found until the next morning. We interviewed the three staff members and the cleaner but they all had good alibis and we couldn't find any connection between them and the victim."

"And you think this John in the hospital did it?" John asked. Sherlock scowled slightly; he disliked that the current victim shared a name with his husband. Objectively he understood that John was a common name but he felt protective nonetheless. John was his.

Lestrade shook his head.

"I wish we did," he replied. "The case went cold because there were no prints on the knife used to kill the victim, nor anywhere around him. But there were a number of prints in the office that didn't belong to anyone who worked there. At least five different people. One of them may have been John Doe."

"May?" Sherlock enquired.

"It's a partial match."

"How close?"

"Ten points."

Sherlock scoffed.

"Useless."

"It's the closest thing we've had to a lead in twelve years."

"You didn't work this case before, Sherlock?" John asked. Sherlock shifted his eyes to Lestrade, raising both his eyebrows.

"It was right before I met you," Lestrade replied.

"Hmm," Sherlock said noncommittally. "Not much of a lead, Lestrade. Twelve years and a partial fingerprint which may or may not tie your man to an unsolved murder in which he was likely not involved. He could have been in that office for any reason. Could be entirely unrelated. Maybe he was a thief. Maybe the gallery was being used for other purposes the staff did not know about."

"We did interview the gallery owner," Lestrade said. "She knew nothing about it being used for anything else. If it was him, though, I'd like to know why he was in London."

"What do you mean?"

"His accent. He's from up north, we think in or around the Manchester area. It would explain why we haven't been able to track him down yet."

Sherlock rolled his eyes.

"And it's not at all possible that he has good reason to travel to London on a regular basis? It's hardly a suspicious activity."

"It's all we've got."

"What you've got is nothing," Sherlock snapped. "Tenuous at best and unlikely to be of real value. It is equally possible that the fingerprint you've so tentatively matched to your current victim is not his and the two events are entirely unrelated."

"Sherlock, we have a missing person –"

"No, you've found a person. He can hardly be missing if you know where he is."

"His family will be missing him."

"You don't know that he has a family!"

"He's wearing a wedding ring!"

"He's wearing a ring. You assume it's a wedding ring because it's on his left ring finger. Could be divorced. Could be a widower. He could be wearing it as affectation. Maybe he has children. Maybe he doesn't have children. Maybe he has a spouse. Maybe he doesn't. You don't know because he doesn't know."

"Just come interview him. See what you get out of him."

"What sort of information do you imagine I'll get from a man with no memory? Any deductions I make will be based entirely on what he's thinking now and may not reflect any previously held opinions or preferences. And you seem to be doing surprisingly well for yourselves; you've already determined where he may come from."

Lestrade gave him one of his put upon looks, which Sherlock ignored. John was far more proficient at those. In fact, John was giving him quite a pointed look now. Sherlock attempted to dismiss this as well, but he could feel John's level gaze focussed on him. He thought he ought to feel more annoyed by how easily John could wear down his resolve, but part of him found a paradoxical pleasure in it.

"He asked for you specifically," Lestrade said.

"What?" Sherlock demanded, sitting up straighter in his chair, noting automatically that John stiffened as well and uncrossed his arms. Lestrade had an irritating gleam in his eye, a moment of triumph at being able to startle the consulting detective.

"He remembers a grand total of four things: snow, lights, the name John, and the name Sherlock Holmes."

"What?" John echoed. "How?"

"Good question," Lestrade sighed. "One of your clients?"

"I did say I didn't recognize him," Sherlock retorted, nodding the file that Lestrade was holding.

"You remember all your clients' faces?" Lestrade arched a disbelieving eyebrow at him and Sherlock scowled.

"I don't need to," he sniffed. "I have a laptop."

"Care to explain how he knows your name then?"

"Lestrade, I have a website and a memorable name. John has a blog with a very active readership – you should know, you read it religiously. Anyone with access to the internet could find me."

"It's possible he was coming here to see you."

"It's possible. If he were, I did not know about it." Sherlock paused then sighed. "Oh, very well. I will go round this afternoon and speak to him."

"And you'll call Donovan before you go," Lestrade warned. "This is her case."

"And yet, she's not here," Sherlock pointed out, spreading his hands slightly.

"Call it a favour for a friend," Lestrade replied and Sherlock smirked.

"We'll call her," John promised. The detective repressed a sigh. John was always so accommodating of Lestrade. Occasionally it was good to put the DI off his stride. It built character.

"Thanks," Lestrade said. John showed him out and Sherlock waited until John was back in the flat before pushing himself out of his chair at the doctor. He grabbed his husband's face, planting a triumphant kiss on John's lips, then began pacing the flat, a gleeful smile tugging at his lips.

"A man with no memory and a connection a twelve year old unsolved murder?" John asked. "You really expect Lestrade to believe you find that boring?"

"I can hardly allow Lestrade to think he'll catch my attention with every case. He must muddle through on his own occasionally," Sherlock pointed out, ignoring John's sarcastic snort. He paused in his pacing, tapping his index fingers together, then pressing them against his lips.

"Imagine, John, just imagine! Over a decade and the first lead they have is a victim who remembers nothing. A man who does not know himself but who knows me." He gave John a bright grin. "This is going to be brilliant."

"You'll have to go easy on him," John said on their way into the hospital. Sherlock glanced down at him with a mild scowl. "I mean it. He's been badly hurt and has no memory."

"Yes, John, I'm aware of that," Sherlock said dryly.

"Just reinforcing the point," John replied. Sherlock sighed and rolled his eyes but John gave him one of his sharp Behave looks.

They were met outside the room by a displeased Sally Donovan, who shot her normal glare at him, dark eyes narrowed.

"Yes, good afternoon to you, too, Inspector," Sherlock drawled. She raised her eyebrows at him, pursing her lips. He could see her withholding a retort about how he should not be here and it delighted him that his presence galled her.

"Don't upset him," she warned.

"What could be upsetting to a man with no memory?" Sherlock enquired. "He doesn't remember what he likes or dislikes."

"Holmes!" she snapped and he gave her a bright little smile. The constable guarding the door let them in and Sherlock saw Donovan hesitate for a moment, as if she meant to join them, so he shut the door behind him with a definitive click, catching her aggrieved expression through the small window.

Sherlock evaluated the patient rapidly as he began to stir at the sounds of people in his room. Precisely as Lestrade's file had described him: early to mid-forties, average height, average weight. His hair was hidden by bandages, as was one of his eyes. From the file, Sherlock knew these were both brown. He glanced at John and frowned slightly: the entire description – except the height – matched his husband.

Difficult to tell anything else, not while the victim was lying down and injured. Any stiffness from old injuries was masked by the new ones, any hint of how he carried himself was wiped away by the present inability to stand. Silver ring on his left ring finger, plain – could be a wedding band, could just be a ring. Impossible to tell unless he could look at it more closely. Nothing distinctive that he could see, no visible scars or tattoos but most of his body was covered with blankets and pyjamas where it was not masked with bandages and tubes.

He opened his good eye and focussed on them slowly.

"Oh," he said, his accent discernable despite the exhaustion in his voice. "More police?"

"No," Sherlock said, giving him a tight smile. "Sherlock Holmes. I believe you asked for me."

He blinked, frowning, before realization settled slowly into his bruised and tired features.

"Oh. Yeah. Remembered your name."

"Do you remember why?" Sherlock enquired coolly. The man stared at him and gave his head a single shake.

"No," he whispered, then cleared his throat. John, ever cognisant of a patient's needs, circled the bed and helped him with a glass of water. The victim's gaze moved to John curiously. "Who are you?" he asked.

"Doctor John Watson," Sherlock replied and John Doe looked back at him.

"One of my doctors?"

"No, I work with him," John replied. "Do you mind if I have a look at your chart?"

The patient shook his head and John plucked the clipboard from the end of the bed, eyes skimming over the pages. The victim watched him in confusion for a moment, then turned his gaze back to Sherlock.

"Sorry, why would I know you?"

"You don't," Sherlock replied. "Never met you before in my life."

"But I knew your name."

"Yes."

"Why?"

"You tell me," Sherlock replied, earning a brief, sharp glare from John. The patient looked at him, tired and puzzled, then sighed softly.

"I don't know," he replied. "If I don't know you, then why do I know your name? What do you do?"

"Consulting detective," Sherlock said shortly. John Doe frowned.

"I don't know what that is," he said.

Sherlock gave an irate sigh.

"No. You wouldn't."

John looked up at him again, brown eyes quizzical, and Sherlock flashed him a disgusted look.

"Useless," he said.

"What?"

"Lestrade asked me to come see what I could deduce – the answer is nothing. He remembers nothing, so there's nothing to determine. A partial fingerprint and a man whose memories average out to one per decade? Could be anything, so probably nothing." He huffed, throwing himself into one of the uncomfortable hospital chairs, slouching down and folding his arms.

"Sherlock –"

"Oh, by all means, review his chart, John. See if you can determine anything about his past based on incomplete medical information. There's nothing here for me. Boring."

"Sherlock!"

"Boring!"

It had been so promising, too. He felt cheated and slouched down further, shooting John an angry glare. John gave an exasperated sigh in return, expression demanding that Sherlock be reasonable, but what John considered reason was often simply pandering and overly patient. He'd been close, so close, to an interesting case, one that might have made him really think – only to run up against a wall immediately.

The victim might be interesting if he were hiding anything. But he wasn't playing at ignorance. He was ignorant.

"Sherlock –" John tried again.

"I could stand here all day going round and round in a circle with him because I don't know anything about him and he doesn't know anything about himself. What would you have me do, John? There's nothing here to work with!"

John gave him a warning look and Sherlock glanced at the patient again, who was watching with shock and dismay. Why dismay? He knew he remembered nothing – surely hearing it from someone else was not so unexpected.

He scowled, annoyed with Lestrade. This was all his fault.

John narrowed his eyes at him and Sherlock huffed in return, refusing to be put off. He was not about to waste his time chasing uselessly after wispy phantom leads.

"Can you tell me what you do remember?" John said, turning back to the patient on the bed. Sherlock swallowed on his irritation; they were wasting their time. He was well aware they had nothing better to do that day – Christmas shopping did not count as better – but he had no desire to stay.

The patient shook his head.

"Just snow and lights," he said.

"Well, what about the snow?" John asked. "Was it on the ground or falling?"

The patient frowned slightly, then sighed, tilting his head back into his pillows. Sherlock was tempted to point out that John had been the one to insist on going easy on John Doe.

"Falling," the other man murmured. "Slowly, y'know? Big fluffy flakes."

"What about the lights?" John asked. "Were they outside with the snow?"

John Doe was silent for a moment and Sherlock could see he was beginning to drift off but forced himself back awake with hard effort.

"No," he said, his voice laced with fatigue. "Like those." He pointed upwards vaguely, to the humming fluorescent lights above them.

"Probably in the hospital then," John said. "That's a good sign. You remembered the name John, too."

"They told me that," he murmured. "I don't remember saying it."

"It says you have some previous injuries that are consistent with military service. Does that ring any bells?"

"They said I was shot in the leg," the other man replied. He coughed lightly, wincing as he did so. John gave him so more water, helping him drink it slowly. Sherlock sighed and tilted his head back, staring at the ceiling, feeling a flash of annoyance that John was ignoring him in favour of a man with no memory. "I don't remember that."

Of course he doesn't, Sherlock thought with an inward scowl but John asked he could check the old injury anyway. Sherlock closed his eyes, refusing to be put off. He heard John pulling back the blankets and shot his eyes open, sitting up and refocusing quickly. He was not about to let John undress a strange man in his bed without supervision.

"Here," John said and the other man's eyes focussed just above his right knee. "Looks about five or six years old, healed well." The patient nodded but there was no flash of recognition in his eye, no indication in his features that he had any memories of the wound.

"Sorry," he whispered. "Nothing."

John nodded.

"It takes time," he said. "Don't worry."

The patient managed the barest of small smiles, his good eye starting to droop closed.

"That's what the DI said, the woman."

"Donovan," John supplied.

"Yeah, that's her."

"Get some rest," John said. "It's the best thing you can do for yourself. We'll be back. Don't worry. We'll get to the bottom of this."

John Doe nodded vaguely and closed his eye as John spread the blankets back over him. He watched him carefully with that Doctor John expression, until he had fallen asleep, his breathing deepening, the heart rate measured by the monitor slowing. Sherlock heaved himself out of his chair, tugging vaguely on his coat.

"Can we go now?" he snapped.

"What was that?" John asked as they strode out of the hospital. He was hurrying to keep up with Sherlock's quick pace, looking up at the detective, squinting slightly in the weak December sun.

"What?" Sherlock snapped.

"That!" John repeated and Sherlock glanced down at him with a mild scowl. "This morning it was all 'John, this is brilliant!' then five minutes in and you decide it's boring? What's so boring about a locked room case where the only connection is a man with no memory?"

Sherlock stopped abruptly, slipping his hands into his pockets and sighing, his breath condensing as it escaped his lips. John had to stagger to a stop and turn back, frowning up at him.

"I suspected he was lying," Sherlock said.

"Sorry?"

"Lying, John, I thought he was lying. Rather, I thought he was lying to Lestrade and Donovan, faking the lack of memory. If he had been, we may have had a starting point. The question would have been why lie to the police? What would he have to hide? If he is connected with this unsolved murder, then likely quite a lot."

"But you don't think he's faking it," John said.

"No, he clearly is not," Sherlock replied. "None of his reactions were based on established preferences or opinions. Every single reaction he gave us was in response to a prompt we gave him."

"What do you mean?"

"He volunteered absolutely no information. Not because he's attempting to convince us that he has none, but because he does not remember anything."

"Couldn't that be too perfect?" John asked.

"Only if he were an exceptionally capable actor able to use his skills following a severe assault. He was waiting for us to give him clues as to how to react because he does not know how to react. My name clearly means nothing to him despite the fact that it is one of the few things he recalled on his own. He was able to provide you with some scant details concerning his visual memories, but only after you enquired. He showed no emotional connection to his old wound. He might as well have been looking at a stranger's injury. If he were faking this, he would have tried to make the responses seem more genuine by adding a touch of detail. This was not lack of reaction because he's attempting to deceive us, it was lack of reaction because he has none."

"But – aren't you interested in why he knows your name?"

"Not especially."

"You're one of four things he remembers, Sherlock! It must be important!"

"Why? Do you think remembering the snow or the hospital lights is important? Do you imagine those play into his assault? His recollection of my name could be entirely coincidental – perhaps he knows someone whose case I investigated or perhaps he read it somewhere. His memories are nonsensical and unrelated."

"That would be a hell of a coincidence," John said.

"Just as it would if it were his fingerprint at Lestrade's old crime scene," Sherlock sighed. "But coincidences happen all the time, John. What if another DI had taken the case rather than Donovan, one who does not know me? Then we wouldn't be here having this discussion and his memories would amount to two names and two visual recollections. Nothing more."

John sighed and bundled his hands into his pockets.

"Well, the police have his fingerprints. If he was in the military, Mycroft could run them."

"If you wish to offer my brother's services to Lestrade, feel free," Sherlock sniffed. "I am not being dragged into that. Any contact with Mycroft before Christmas always results in him insisting we celebrate the holidays together."

John tried to repress a wry smile but failed.

"All right, I'll ask him," he said. "Come on. It's freezing. Let's get a cab and go home."