"Have you got anything for us on that case yet?" Lestrade asked as he stood in the doorway of 221B.
"Which case?" Sherlock asked without looking up from a large hardback book that he'd been reading.
Lestrade rolled his eyes in frustration, "The murder case. The woman that was killed." he said with a frown.
"Oh. That." Sherlock replied casually, "It slipped my mind. I'll look into it again when I have some free time."
"Free time?" Lestrade shouted, "A woman has been murdered and I need your help! I can't just wait around for you to stop reading your books!"
"I'm sorry Geoff, but I'm currently working on a case that is more interesting to me." Sherlock replied, finally looking up.
"It's Greg!" Lestrade shouted, "Fine, we'll do this without your help."
"Lestrade, is everything alright?" John asked, walking up the stairs behind the Detective Inspector.
"Sherlock has decided that he's no longer interested in finding the killer of that poor woman." Lestrade said in frustration, darting down the stairs once John had reached the landing, "Sociopath." he added in a mutter.
John watched Greg walk away down the stairs and waited for the front door to slam shut before he entered the living room.
"He's not going to drop it." John sighed.
"I know. I just need to stall him so we can work out what we're going to do." Sherlock replied, getting to his feet and pacing.
"What we're going to do?" John asked, "I don't know what you're going to do but I'm going to hand Mycroft over to Lestrade."
"You can't do that." Sherlock said, watching his flatmate with a frown.
"Yes I can." John replied as he boiled the kettle in the kitchen.
"No, really, you can't. You'd be taken off to a secure Secret Service prison." Sherlock said, walking into the kitchen, "Mycroft won't be found out. He can cover it up easily."
"Then what do we do? Just because he's a serial killer doesn't mean that he's above the law." John replied.
"Your brother is a serial killer?" Lestrade said from the doorway, watching the two of them with a frown, "You've got a lot of explaining to do, Sherlock."
"I thought you'd gone?" John said as he whirled around in surprise.
"Nice detective trick, Lestrade." Sherlock muttered, "You used the sound of the kettle boiling to hide your footsteps."
"You can't tell anyone about this." John said, looking from Sherlock to Lestrade.
"I'm a cop, John. I can't hide a suspect!" Lestrade shouted, running a hand through his hair, "You need to explain everything, right now, Sherlock."