The air in the classroom felt like a spring that had been compressed for an entire lesson and finally allowed to loosen a little. Some students began packing their bags, some stood and headed for the door, and some exchanged a few quiet words. Harry remained in his seat. His gaze rested on the word on the slate-the only word Severus Snape had written that day, without explanation or annotation. It lay alone in the middle of the black background, like a chess piece set on an empty stretch of ground.
He committed the shape of the word to memory. He intended to look it up when he got back.
Shortly after class, Filch stood in a converted storeroom on the castle's first basement level. The sign on its door read "Temporary Storage for Discarded Teaching Equipment," but inside, space had actually been cleared for a table and a chair. Beside him lay his brand-new logbook with its gilt-lettered cover, still bearing fingerprints from when it had been leafed through the previous day. He held himself unnaturally straight, with the sort of posture someone unconsciously adopted while waiting for a decisive moment to arrive.
The door was pushed open from outside. The pressure was steady, like a signal transmitted from somewhere far away. The person who entered wore a gray traveling cloak, its hood covering most of their face and leaving only the lower part of their jaw and lips exposed-the lips were pale, the line of the mouth flat. The visitor did not look at Filch, but went straight to the table and laid a rolled parchment on it. A dark red wax seal secured the seam.
Filch's gaze fell on the wax seal. It bore a symbol he had never seen before: a circle with a curved line