Cops and Robbers
John was awoken at some ungodly hour in the morning (don't look at the clock or you'll have to explain why you killed your flatmate) to the sound of something that wasn't a bullet hitting the wall with considerable force. He stumbled downstairs to find Sherlock throwing various scorched books, pens, and what appeared to be the leg of his chair at the wall, while a pan on the stove smoked ominously.
"Sherlock, what the bloody hell-"
"They're all bugged."
"Mycroft bugged them all while we were away on our last case, and I haven't even searched the bedrooms yet. That-" (what followed was a creative combination of curses not usually heard unless one is outside a Glaswegian pub at 11pm on a Saturday night, and only if the booze is extremely cheap and two people who have an unhealthy level of hatred for one another happen to try to flirt with the same girl.)
John was impressed by Sherlock's grasp of modern language in all its filthy splendor, but moved to draw the detective back to the matter at hand when it looked like he may be running out of air. "Why would he bug the flat?"
"-weasel-shagging idiot with the metal capacity of a leaking garbage disposal and all the charm of a rusty spoon. Probably because he wants to keep an eye on me for anything he could use to blackmail me into doing a case for him, I don't know. Could you take that pot off the stove, please? The microphones should have dissolved by now."
Sure enough, when John picks up the saucepan, it contains the remains of what might have been several very expensive microphones. He doesn't want to know what they're soaking in and just hopes that it doesn't eat through the pot too quickly.
Mycroft turns up half an hour later after Sherlock sends him some very rude texts, with not-Anthea in tow. Surveying the damage, he quietly remarks "The last time you caused this much destruction of household items was that time you were conducting your experiments with electricity and its relation to acid strength."
John suddenly worries for the light bulbs. "When was this, exactly?"
"He was six at the time, I believe."
Sherlock swirls around to shout at his brother, seeming only to reconsider it at the last minute. "These bugs really don't do any good, Mycroft. I'm only letting you keep tabs on me because I know you'll start kidnapping people if you can't."
Mycroft raises a single, expressive eyebrow. "You're letting me, Sherlock?"
"Yes." The answer is unwavering. "I could disappear this very moment if I wanted to."
John almost groans. He has a feeling where this is going…
"Well then, dear brother, how about we test that theory?"
It just went there.
"Let's see if you can remain out of my hands for twenty-four hours. You'll have a fifteen-minute head start."
Sherlock's eyes light up, even though he is desperately trying to maintain his calm position. "And if I do?"
Mycroft smiles in the indulgent-older-brother way that gives John an overwhelming urge to punch him. "I'll scale down the in-flat surveillance that I have on you two." He pauses. "And I'll completely remove all of the bugs for one week."
Sherlock looks at him. "That's too good to be true… if you should win, what's my penalty?"
Mycroft smiles. "I wouldn't penalize you, dear brother. However…"
Here it comes, John thinks.
"I would be extremely appreciative if you could be of assistance in the next few matters I bring to your attention."
Mycroft turns to leave. "The rules are simple. You have to remain out of my custody for twenty-four hours. I'll be generous and give you a half-hour start-you'll need it. I'll ignore anything that isn't too illegal, but in return, I won't be pulling any punches."
He checks his watch as he strides out the door. "Let the record show it is now 4:18 am. See you soon, dear brother."
Sherlock grins. "Not as soon as you think."
Love it, hate it, have a prompt for it, leave your opinion in a review. There will most likey be 24 chapters, and I'm going to try and write a variety of genres: drama, action, maybe even some fluff if I can work up the courage.
Let the chase begin!