Trouble on the home front

On the first Monday in December, the Thief's Downfall arrived.

Dumbledore announced the news himself at breakfast.

He tapped the rim of his goblet.

He waited until the chatter in the Great Hall had subsided to a suitable level, then spoke in the tone of someone introducing a new flavor of dessert:

"This morning, a new security installation will be fitted in the Entrance Hall. Donated by Mr. Rowle and installed by the goblins of Gringotts, it can wash away the vast majority of disguises, illusions, Polyjuice Potion, and unauthorized magical concealments."

Fred immediately raised his hand. "Professor, can it wash away unfinished homework?"

"I'm afraid not."

"Then its functionality still needs improvement."

George sounded disappointed as he added this from beside Fred.

Snape stood at the edge of the High Table, watching the restless students below with a cold gaze.

He had already intimidated several troublemakers with a look, giving them an advance warning.

Gavin sat at the Hufflepuff table and stuffed the last mouthful of rice noodles into his mouth.

It's finally here.

That was the only thought in his head.

After the events of the first half of the year, he had completely lost faith in Hogwarts' security measures.

And the corpse that had mysteriously vanished left him with a lingering sense of unease.

Now that they had this thing, at least no one could slip into places they shouldn't be wearing someone else's face.

At least, that was how it appeared.

An hour later, the Entrance Hall was packed solid.

The installation itself had actually gone very smoothly—

Two goblins in Gringotts uniforms had erected an archway just outside the castle's main doors. A curtain of water flowed continuously from its top into two newly carved stone basins below.

The water was a very pale silver,