Cleaning the Hogwarts castle from the top of the tallest tower to the bottom of the lowest dungeon didn't break the spirits of the Official Hogwarts Pranksters. It did serve however to familiarize them with just about every nook and cranny of the castle.

It was less than two days after they had finally finished their months long task and first year was nearing its end that they sat down and began to plan the pranks that they would soon implement.

It was also during this time that Albus, Dryfus, and Horus began drawing a map of the castle from what they remembered cleaning. Sherlock and James were excluded from the mapmaking process because of their lack of artistic skill and their constant ludicrous suggestions. After Sherlock had once again suggested adding everyone in the castle and their locations and James had once again suggested making it only become visible with the proper password, Albus threw a copy of Hogwarts a History at them in frustration. As far as he was concerened, all they needed was a simple multileveled map.

Sherlock and James miffed at not being included in the mapmaking committee decided to wander about the castle on their own, causing mischief wherever they went. In the Divination classroom, they turned Professor Entwhistle's crystal ball into a fishbowl complete with goldfish. Not knowing how they did it as they had meant to turn it into a bowling ball, they left it as it was. In the Defence Against the Dark Arts room the practice dummies for the advanced students were later found wearing women's underwear, and the Fat Lady who guarded the portal to the Gryffindor common room ended up sporting a rather fine handlebar moustache for two weeks.

Eventually the mapmaking session was over, and Holmes and Moriarty were welcomed back to the group for the marathon prank planning session that had lasted until curfew.