It had been much too long since the last rain. The storm was crackling over London, making things bloody humid, but it just wouldn't break. When it did, it would surely be a sudden downpour, so every step outside felt like cheating the devil.
John had planned his route home from the clinic ahead of time, making sure to pass by every covered walk possible in case he had to resort to running from safe house to safe house. He could have called a cab, but that would have been, in Sherlock's words, dull.
Except for a heightened sense of danger in an otherwise mundane aspect of his life, his preparation was in vain. Not a drop had fallen by the time he reached the flat. The same could not be said for the kitchen.
"What is it now?" John shouted. He followed the sound of coughing to the center of the smoke cloud that was once their kitchen. He was hyper aware of the stickiness beneath the soles of his shoes and was eternally grateful that he had kept them on.
A few waves of a newspaper dissipated the smoke around the detector, revealing that it had been dismantled. The explosion must have been intentional. John cough-sighed. At least Sherlock was concerned enough not to bother Mrs. Hudson while he was conducting experiments on combustion. Or maybe disabling the alarm was so that she wouldn't bother him.
"You're back, good," Sherlock emerged from the smoke. He was waving a hand in front of his face to clear a breathing path, but was otherwise looking quite content.
"Good? Sherlock, what's happened to our kitchen?!" John said between coughs.
"Nothing irreversible," Sherlock assured him. "Wait until the smoke clears."
"Help me clear it out, then?" John began to reach for a stack of papers to use as fans. He didn't particularly care about how important what was written on them was right now.
Sherlock quickly stepped around the table and grabbed his shoulders, halting his movements. "It'll dissipate soon enough."
John gave him a look. "What do you mean," he asked flatly.
"It's an experiment on the reliability of a smoke screen over time," Sherlock lied.
"Then why don't you have a stopwatch running?"
"Got me," Sherlock dropped his arms. "It's an adhesive experiment."
"An adhesive...?" John looked around for what he could possibly be gluing. Then he looked down.
"I will punch you," he promised Sherlock.
"If you can reach me," Sherlock reminded him. He didn't seem too worried by John's threat. Sure enough, John's shoes were firmly planted to the floor boards.
"Hold on, you were walking on this stuff too," said John, seeing a greenish film across the floor in a square meter around him. "Why aren't you stuck?"
"The set time for the adhesive correlates with the dissipation time of the smoke," Sherlock explained. "As long as I stayed moving, I was in no danger of getting caught."
John grumbled, but decided not to punch him after all. He bent down to untie his shoes, being careful not to set his knee in the stuff. Suddenly he was lying on his side, having been pushed to the ground by Sherlock.
"What are you...?!"
"That's perfect, John," Sherlock complemented him. John heard the click of a phone camera followed by a ruffling of papers. Sherlock sat on his heels next to where John had fallen.
"Look at this, John," he said, holding his mobile and a photo of a crime scene next to each other to be compared. The body of the crime scene was in the same position on his side that John was in the photo. "That's the method of disarming the victims. The shoes of both victims were taken shortly after, most likely to destroy the residue of the adhesive. The nature of it is to dissolve on anything but the rubber that makes up the underside of shoes. Creative, but not untraceable."
John regained some dignity by pushing himself up to an awkward, twisted-leg sitting position. His feet were still trapped to the floor at an uncomfortable angle. It didn't stop his arms from pushing Sherlock over.
"Glad I could help, not how do I get my shoes unstuck?" John asked.
Sherlock got to his feet. "You can't."
"I can't."
"The only way is to burn them off the floor," Sherlock said simply. "The murderer laid out a camouflaged mat with the adhesive on it that they could unbolt from the floor to take the shoes away. They don't separate in a condition to be worn again."
"And you've found a way around that, then?" John said expectantly. He yanked both his feet from his shoes without bothering with the laces.
Sherlock shock his head minutely. The unspoken words on his face were, "was I supposed to?"
The words on John's face had a lot more to do with murder.
"Also," Sherlock began, attempting to move away from the subject quickly.
"Also?" the one word was laced with land mines.
"Also, we have somewhere to be," Sherlock informed him. "Take these," he handed John a pair of old shoes off the table, "we're already late."