“See you in Honeydukes,” said George, winking.

They left the room, both smirking in a satisfied sort of way.

Harry stood there, gazing at the miraculous map. He watched the tiny ink Mrs. Norris turn left and pause to sniff at something on the floor. If Filch really didn’t know . . . he wouldn’t have to pass the dementors at all. . . .

But even as he stood there, flooded with excitement, something Harry had once heard Mr. Weasley say came floating out of his memory.

Never trust anything that can think for itself, if you can’t see where it keeps its brain.

This map was one of those dangerous magical objects Mr. Weasley had been warning against. . . . Aids for Magical Mischief-Makers . . . but then, Harry reasoned, he only wanted to use it to get into Hogsmeade, it wasn’t as though he wanted to steal anything or attack anyone . . . and Fred and George had been using it for years without anything horrible happening. . . .

Harry traced the secret passage to Honeydukes with his finger.

Then, quite suddenly, as though following orders, he rolled up the map, stuffed it inside his robes, and hurried to the door of the classroom. He opened it a couple of inches. There was no one outside. Very carefully, he edged out of the room and behind the statue of the one-eyed witch.

What did he have to do? He pulled out the map again and saw, to his astonishment, that a new ink figure had appeared upon it, labeled Harry Potter. This figure was standing exactly where the real Harry was standing, about halfway down the third-floor corridor. Harry watched carefully. His little ink self appeared to be tapping the witch with his minute wand. Harry quickly took out his real wand and tapped the statue. Nothing happened. He looked back at the map. The tiniest speech bubble had appeared next to his figure. The word inside said, “Dissendium.”

“Dissendium!” Harry whispered, tapping the stone witch again.

At once, the statue’s hump opened wide enough to admit a fairly thin person. Harry glanced quickly up and down the corridor, then tucked the map away again, hoisted himself into the hole headfirst, and pushed himself forward.

He slid a considerable way down what felt like a stone slide, then landed on cold, damp earth. He stood up, looking around. It was pitch dark. He held up his wand, muttered, “Lumos!” and saw that he was in a very narrow, low, earthy passageway. He raised the map, tapped it with the tip of his wand, and muttered, “Mischief managed!” The map went blank at once. He folded it carefully, tucked it inside his robes, then, heart beating fast, both excited and apprehensive, he set off.

The passage twisted and turned, more like the burrow of a giant rabbit than anything else. Harry hurried along it, stumbling now and then on the uneven floor, holding his wand out in front of him.