A/N- I asked a friend for a 15 minute prompt before a class and she replied with "Swooshy coat stealing, Mycroft vs Sherlock. Oh, also a rubber duck." So, 15 minute dialogue only exercise. I thought it was amusing. Think it's fairly clear, but Sherlock starts.
I promise I'm working on really stories too.
"You're being childish."
"When one is dealing with a child, Sherlock…"
"Give it back."
"Give Detective Inspector Lestrade his evidence back."
"It's not like he was using it for anything useful!"
"Removing evidence from a crime scene is, well, a crime, isn't it?"
"It won't matter when I solve the case. Now get out, I have to go somewhere."
"Out in this weather with no coat? What would the good doctor say?"
"Leave John out of this."
"I'm merely expressing my belief that your friend cares about your well-being."
"If you're so worried I'll catch my death just give me my coat back."
"Evidence first, then coat."
"This is revenge, isn't it?"
"For the duck."
"Sherlock, what are you talking about?"
"Feigning ignorance doesn't suit you, Mycroft. The rubber duck I melted."
"That was a very long time ago. I would never stoop to such petty behavior."
"Because there is nothing petty about stealing my coat?"
"Not the way I'm doing it. You tell me where the evidence is; I'll tell you where your coat is."
"Under the couch. I suppose you want me to get it for you?"
"Take it. Coat?"
"I knew the reasonable place for coats would be the last place you'd think of."