John laughed, grinning. "That actually sounds great. We'll have to find somewhere to meet up, find all of the good hiding places." He said, actually getting a gleam of excitement and mischief in his eyes. He watched Sherlock as he spoke, still smiling. "That actually sounds kind of interesting, Sherlock. So you want to be a... detective?" He didn't know what they were exactly called in the wizarding world. "Or... what are they called? I swear I've seen the term in a book somewhere." He said thoughtfully, searching back in his memories for the book he had read. It started with an 'a', hadn't it? "I guess you are right, though." He said with a smile. "If they don't expect it they can't really prepare for it. They'd probably be completely oblivious to what you're doing."