Sherlock retrieved gun that had skittered across the cement floor of the parking garage. He crossed the space between them with resolve, even as the man's taunts of "You're a detective, not a killer" quickly changed to "Please! No!" as Sherlock neared. Sherlock dispatched him with one shot. Logically, it was the only answer that made sense. He left him there. Sherlock walked along the river that ran through the city. He dropped the gun and his gloves in different locations.
He made his way back to the rent-by-the-week flat that was his base of operations. He walked in, hung up his leather jacket and grey scarf, and proceded to enter the bathroom and promptly vomit in the toilet. His stomach was mostly empty to begin with, so it didn't take long.
Sherlock grabbed a bottle of water and sat down at his laptop. He ran over his notes and started booking a flight to the next city on his agenda. As the flight info was processing, Sherlock found that he had picked up a pen with his right hand. He was tapping it rapidly on the table top. He focused on the pen and slowed the rhythm. His breathing slowed as well. The tapping took on the beat of Bach's Violin Sonata No.1.
He looked around his cluttered workspace. Finding not one blank piece of paper left, he turned to the bookshelf. Other temporary inhabitants had left their unwanted paperbacks. Sherlock grabbed a cheap romance novel and tore out an extraneous print-free page from the back of the book. He sat down and picked up the pen. The tip hovered above the yellow-rimmed page, gently trembling. Finally he started to write in ghost letters.
"He wasn't a very nice man, John. You would understand. I'll do whatever needs to be done to keep you safe."
Sherlock picked up an envelope at the airport and dropped it in the post minutes before his flight took off.
The next time Sherlock had to take a life, he didn't feel the need to write home about it.
Some time and a few cities later, Sherlock was on a necessary but very boring stakeout. He sat at a cafe by the window and ordered a cup of tea. When it arrived, Sherlock was distracted by the scent. Hundred of miles away from Baker Street, somehow he was served a cup of the same brand and flavor of tea that John always brought home from the shops. Although John Watson was a practical and frugal man, it was a good tea. Sherlock cupped it in both hands and breathed it in. He closed his eyes and was transported back to his kitchen table, bent over his microscope, where cups of tea would appear at his elbow like magic, often accompanied by a biscuit and a pointed clearing of a throat that ordered him to consume something.
Sherlock was so lost in his revelry he almost missed the woman he was waiting for as she slipped out the back exit and skirted across the alley. He did get the plate number on her rusty volkeswagon and noticed clear signs that it had recently been in the country side, most likely someplace with both sheep and ducks judging by the clump of mud that had dropped from her wheel well as she hit the curb as she sped away. After retrieving said mud, Sherlock stole back into the cafe. He took one last sip and ripped the tag from the tea bag. He also tore a page from the order book that the waitress had dropped from her apron.
That night he huddled in the cold, curled in the front seat of his "borrowed" SUV. He was parked in the brush down the lane from the farm house. The sheep and ducks were sleeping, but there was a boisterous party going on inside. One of the cars out front was a rusty volkeswagon. When the party died down and most guests were gone, he would sneak in and hit the safe. In it was a flash drive that Sherlock needed.
Sherlock took out the slip of thin paper and the tea tag that he had shoved hastily into his back pocket. He found a pen in the glove compartment. He rubbed his hands together to improve the circulation in his frigid fingers. By the light of the moon, he looked at the small scrap of paper.
"I don't know if I ever said thank you when you made me tea. I will say thank you next time. I won't always remember to, mind you, but I'll always will appreciate it. You make very good tea, John."
Sherlock lifted the tea tag to his nose and sniffed deeply. For just a moment his eyes stung a bit. It must have been from the cold. Very carefully, as if it were a prized four leaf clover that a child pressed in the pages of a dictionary, Sherlock folded the note around the tea tag. He placed it in the breast pocket if his shirt. Later, after he stepped over about half a dozen passed out party-goers on his way to the safe in the study, Sherlock snatched one envelope from the desk.
There were more capers along the way that Sherlock felt moved to send along word to John about. There was the escape in Scotland that actually involved Sherlock using the fencing skills he learned in his youth. There was the boat chase through the canals in Venice. John would have liked that one, even though he is not fond of boats. And there was the disguise he donned in Marakesh that would have made John laugh.
But there were also those lonely, feverish nights in Belarus where Sherlock battled the flu but had to keep moving to different locations to evade suspicion.
"John, you're a doctor, is there any evidence to support that saying about 'feed a cold and starve a fever?' God, I must be feverish to write something so stupid. I miss my bed John. I miss the fireplace at Baker Street. You made me soup once, when I was sick. It was terrible. You canceled your date to stay home and make me terrible soup. Why?"
And then he was caught. It was a stupid miscalculation on his part. He though himself to be so clever. He found his was into the smuggler's warehouse so easily, posing as a lorry driver. But they were waiting for him. Their leader was smarter than Sherlock had given him credit for. They didn't know who he was and never guessed he was working alone. They took turns trying to get him to talk, assuming he was working for some rival.
He was tossed into the storage container after one especially brutal session. Sherlock could smell the Chinese take away wafting from where his captors ate on the hood of a car. His mouth watered and his stomach growled despite the cracked ribs that surrounded them. He tried to organize his thoughts and gather his strength for when they opened the door again. Under his bare toe, he felt a familiar shape. He picked up the dirty yellow pencil with the broken tip. Two of Sherlock's fingers on his right hand were broken, so his grip was very loose. But it felt like holding onto a lifeline. He held it above the paper tag one one of the old wooden crates.
"I know a great Chinese place not far from here. You can always tell by the bottom 2/3's of the door handle." Sherlock chuckled dryly at his own joke before turning his implement back to the paper. "I'm hungry, John. Let's have dinner."
He carefully ripped the packing slip off the contained, folded it up, and stuck it in his one remaining shoe. They had only needed the one foot bared to attach the electrodes. He then snapped the pencil in half and hid it in the palm of his left hand, which only had one broken finger. That night he escaped, and one of his captors lost an eye.
Sherlock drove for about two hours and broke into someone's empty vacation home. He cleaned himself up as best he could, but he knew infection was already setting into several wound sites. He ate a can of fruit and barely held it down. He switched cars and drove over the border and straight through to Amsterdam, only stopping once. He needed to mail something.
He showed up at the door of a posh home. He rang the buzzer and leaned heavily on the door frame.
A woman's voice said through the speaker "I'm sorry but Mistress Kate is not taking any appointments today."
"I'm not here to see Mistress Kate. I'm here to see The Woman." He coughed and everything hurt. "I'm cashing in that favor you owe me"
The door buzzed, the lock clicked open. Sherlock turned the handle on the door and was unconscious before he hit the floor.