I found it highly suspicious that John stayed quiet the whole time at Leinster Gardens, and when the lights went up he didn't look surprised at all. Then I watched the Baker Street scene again, and I suspect that by the time he went over there, he already knew who the shooter was. As always, I explore my theories by writing them down. Enjoy.
Some dialogue taken from His Last Vow. I do not own it.
A Chair In Its Proper Place
Tired, rumpled, and sick with worry, John Watson returned to his best friend's hospital room. He had left Sherlock's bedside for a few minutes, to buy some vile-tasting hospital coffee and call Mary. It was three in the morning, but no one in Sherlock's circle of friends and family was asleep, not on this awful night when they'd almost lost him (again).
The door was ajar. John frowned, remembering that he had closed it before leaving. A rush of terror filled him as he realized that someone had tried to kill his best friend, and that person could very well come back!
He dropped the coffee cup, ready to sneak into the room and take down an assassin, when the sight of a long, black umbrella stopped him.
Mycroft.
"—let your sentiment get the better of you, little brother," the smarmy git was saying. "Doctor Watson, do come in."
He hadn't even turned around. John thought better of asking how he'd known it was him—Sherlock always knew, and John wouldn't give Mycroft the satisfaction of asking.
"Nice of you to visit your brother," John said sarcastically. He knew there was little love lost between those two.
"John," Mycroft said, with the air of an exasperated parent talking to a toddler, "despite appearances, my brother is dearer to me than anyone in this world. The reverse is not true, but then, little brothers are known for being ungrateful."
"What makes you say that?" John asked, curious. "Who knows Sherlock well enough to know whom he loves most?"
Mycroft gave him a look that smacked of pity.
"Did he ever tell you why he jumped from the roof of St. Bart's?" he asked. "I imagine not."
John fought a surge of anger. The false suicide was a topic he hoped never to discuss again. "He jumped to trick Moriarty's people into thinking he was dead, so he could infiltrate the network and take them down from the inside."
"Is that what he told you?" Mycroft Holmes said, decidedly unimpressed.
"Are you saying he lied?" John demanded, his voice rising, "Because I've already forgiven him for faking his death for two years."
"Yes, after making him bleed for the privilege," the elder Holmes brother drawled. "Sherlock did not tell you the full truth. Do you remember the assassins that Moriarty sent to Baker Street?"
"I will never forget," the doctor said, with feeling.
"Three snipers," Mycroft continued. "Three targets, the people Sherlock loved most in all the world. Only two things could call them off: Moriarty's orders, or Sherlock's death. Moriarty shot himself to prevent the first option."
John sank onto his chair. No one had ever told him this. He turned automatically to Sherlock, but there was no answer in the unnaturally pale, still face of the unconscious genius.
"I need hardly add that I was not one of the three targets," Mycroft said, and his tone was even enough to suggest no sadness. His eyes, however, could not hide the truth. "My little brother, the so-called high-functioning sociopath, jumped to his apparent death to save the lives of his best friend, his landlady, and Detective Inspector Lestrade."
"I never believed he was a sociopath," John said hoarsely.
"No one with an ounce of intelligence would believe it," the British Government replied, and there was a trace of venom in it. "I'm glad you know better, Doctor Watson. You will never know just how much my brother sacrificed for you. I've seen evidence of torture and post-traumatic stress, only what he allowed me to see. I know the scars run deeper than that."
John's face had turned completely bloodless. As smart as Sherlock was, he'd always been so far removed from the horrors of battle, at least in John's mind. He could scarcely believe what he was hearing. He had no idea how someone like Sherlock, who hid behind a stoic facade, would deal with the worst of human nature, when exposed to it in such a brutal way.
"When I extracted him from that Serbian dungeon, half-starved and nearly dead, the first person he asked for was you," Mycroft told him. "When he returned to London, he was eager to see you. It never crossed his mind that you wouldn't feel the same; the wounds on his back were still healing when you knocked him to the floor in that restaurant."
John winced.
"Ah, well," Mycroft finished airily. "I've always warned him that caring is not an advantage, and that people will move on and leave him behind in the end. He ignored my advice. I really hope he doesn't regret it later on."
"He won't!" John cried, indignant. "Because he ignored your rubbish advice, he has friends who care about him!"
"We'll see how long that lasts, won't we?" the man replied, sneering. "My best to Mary," he said, then turned his back to John. To the doctor's astonishment, Mycroft smoothed the unruly curls on his brother's forehead, and bent down to whisper something in his ear. Then, with a swish of his brolly, he was gone.
Five days later, John Watson, Martha Hudson, and Greg Lestrade had gathered at 221B Baker Street, sick with worry for Sherlock. He had disappeared from the hospital, only six days after getting shot. Mycroft, Mary, Molly, even Anderson had joined the search, listing every known bolt hole. Mycroft's men, the homeless network, the Empty Hearse, and Mary Watson were scouring London for signs of the detective.
"He knew who shot him," John repeated tiredly. "The bullet wound was here, so he was facing whoever it was," he added, pointing to his chest.
"So why not tell us?" Lestrade insisted, and then it hit him. "Because he's tracking them down himself."
"Or protecting them," John said.
"Protecting the shooter, why?" Greg asked.
"Well, protecting someone then. But why would he care? He's Sherlock. Who would he bother protecting?" John thought aloud.
He sat in his chair, thinking. Who was important enough to Sherlock that he'd protect them, especially at such a high personal cost? Suddenly, John remembered his last conversation with Mycroft Holmes.
"My little brother, the so-called high-functioning sociopath, jumped to his apparent death to save the lives of his best friend, his landlady, and Detective Inspector Lestrade."
What a coincidence, thought John wildly, that all three sniper targets were in the same room tonight.
"Call me if you hear anything," the DCI ordered. "Don't hold out on me, John. Call me, okay?"
"Yeah," John said, distracted. "Yeah, right."
"Good night, then."
"Bye, then," called Mrs. Hudson, following Greg to the door. "John, need a cuppa?"
Only then did John realize that his chair was back in its proper place.
"Hey, what happened to my chair?"
"It was blocking my view to the kitchen," Sherlock had said, surly as a teenager. "You were gone; I saw an opportunity."
"Mrs. Hudson," asked John, "why does Sherlock think that I'll be moving back in here?"
"Oh yes," chattered the landlady, "he's put your chair back again, hasn't he? That's nice. It looks much better."
John went very still. He had just noticed the familiar, moon-shaped bottle of perfume on his table. It was Claire-de-la-lune. A hum of panic was rising in his head. No. No!
"Claire-de-la lune, why do I know it?" Sherlock had whispered in Magnussen's office.
"Mary wears it," John had answered, busy with Janine's head injury.
"John, what's wrong? Tell me. John?" Mrs. Hudson asked, concerned at his prolonged silence.
"You, Mrs. Watson, are in big trouble. His first word when he woke up...Mary!"
No. It's not possible. She would never! Why would she? He was their friend, their best man!
His phone buzzed then, drawing Mrs. Hudson's attention. "That's your phone, isn't it?"
"Protecting the shooter, why?" Greg had asked, not five minutes ago.
"Well, protecting someone then. But why would he care? He's Sherlock. Who would he bother protecting?"
To his knowledge, John realized, the only shooter Sherlock has ever protected was John himself. He'd shot the cabbie. Sherlock had known immediately. He'd helped John remove the powder burns.
"It's Sherlock, John. Sherlock!"
"When I extracted him from that Serbian dungeon, half-starved and nearly dead, the first person he asked for was you."
John had frozen in place, looking straight ahead into his memories. He pulled himself together and his eyes caught sight of the perfume bottle again.
"John?" Mrs. Hudson called again, worried. "You have to answer it!"
John took a deep breath, and answered the phone. There was only one way to know.
"Where are you, Sherlock? Where is she?" he asked, tense.
A sharp intake of breath on the other side told him Sherlock was surprised, or in pain, or both. "You've deduced the identity of my shooter, then?"
"Please, Sherlock," John asked, close to his breaking point. "Just tell me."
"Come to 23 Leinster Gardens, and we'll see if you've deduced correctly."
There was a short pause.
"John—I'm sorry."
That's all for now, folks! I might go on and write about the lost months between the fight at Baker Street and Christmas at the Holmes' house, but I do have another Sherlock fic that I started before the Series 3 madness, and I really want to finish it. lol
Leave some feedback if you're so inclined, it's always appreciated. =)