The Headmaster's Office

"Professor McGonagall, how about... using a fan?" Luo Bin suggested.

"A fan?!! An excellent suggestion!"

Minerva McGonagall waved her wand and conjured a large fan. With one gentle sweep, Nearly Headless Nick drifted 0.3 meters to the right. She handed the fan to Ernie and told him to fan Nick all the way to the Hospital Wing.

Then Luo Bin witnessed a truly extraordinary sight!

Nick moved slowly forward like an uninflated hovercraft, bobbing along in fits and starts. With every sweep of the fan, Ernie jerked his upper body backward, probably to avoid smelling the "exhaust"!

Now only Luo Bin, Harry, and Professor McGonagall remained in the corridor.

"Follow me, Sear, Potter!"

"Professor, I swear I never..."

"Potter, telling me is no use. This matter is now beyond my authority. Come along!"

Professor McGonagall walked so quickly that Luo Bin and Harry had to pick up their pace or risk losing her.

After several twists and turns, the three stopped before a stone door. Luo Bin looked up at it. A narrow seam divided the door down the middle, also splitting a hideously ugly troll's head.

"Lemon Drops!"

The moment Professor McGonagall spoke, the troll's head came to life. Its enormous mouth twisted, and it spat a silver key out of its throat. The key floated up and slotted itself into a recess in the stone door.

Then, with a series of creaks, the stone door slowly opened, revealing an old-fashioned spiral staircase with an air of antiquity!

"Stay close!"

Professor McGonagall entered first, while Luo Bin brought up the rear. Once both his feet were on the stone steps, the door creaked shut again.

Luo Bin had visited the Headmaster's Office several times, but this was his first time taking this route. "Professor, why did you choose this