The first prank happened on a Wednesday.
He noticed it at breakfast: the portraits in the Entrance Hall corridor were, without exception, wearing small pink bows. Not attached to their frames — attached to the subjects within them. Every painted figure in the long corridor from the Great Hall to the main staircase had acquired a pink satin bow, each one slightly different in size and position, as though the decorator had taken their time. Sir Cadogan had one tied to his visor. A Friar on the floor had one on his hood. The series of seventeenth-century headmasters and headmistresses who usually contemplated their painted gardens with varying degrees of satisfaction were now doing so while wearing coordinated pink accessories.
The students passing through the corridor had, collectively, the quality of people who had encountered something that had asked them not to laugh and found the request very difficult to honour.
Umbridge came through at eight forty-two. He watched from his position at the Gryffindor table, which had a clear line of sight to the corridor entrance. She stopped. She looked at Sir Cadogan, bow on visor, who appeared to find the situation entirely consistent with his general approach to the world and had tilted his bow at a slightly more rakish angle than it had been placed at. She looked at the Friar, who was beaming. She looked at the full length of the corridor with the expression of someone conducting a rapid assessment of the magnitude of the inconvenience.
Then she walked to breakfast with the pink smile in place and said nothing.
He noted this. She was either not going to respond to things she couldn't prove, or she was going to respond to everything she couldn't prove, which were two very different administrative philosophies and he needed to know which one she had. He waited.
She said nothing about the bows at all. Which meant she had decided, with the specific calculation of someone who had been in these situations before, that reacting to untraceable pranks elevated them. The portraits were normal by Thursday morning — he suspected Filch, who would have been instructed quietly, and who had the quality of someone following instructions he found insufficient.
The second prank was on Friday of the same week, in Defence.
He was in his third-row seat when it began — a faint sound, low enough that it took a full thirty seconds for the room to register it consciously, because it had been beneath the threshold of deliberate attention when it arrived. It was music. Not dramatic music, not something with obvious comic intent. It was a small precise magical sound, produced somewhere in the walls of the classroom, playing the same cheerful four-bar phrase on repeat at the volume of a music box with the lid slightly ajar.
The phrase was from a nursery rhyme. He placed it at the second repetition: Humpty Dumpty had a great fall.
Umbridge stopped mid-sentence.
The room had by now identified the sound and was doing the specific thing rooms did when they had collectively decided something was funny and were attempting not to show it. The sound had the quality of something placed with care — not immediately obvious, not traceable to any student's hands, installed in the wall with a patience that was almost architectural.
She looked around the room. Thirty pairs of eyes looked back at her with the specific expression of people who were also hearing the music and were also curious about its origin and had no information to offer.
She sent for Filch.
Filch arrived with the specific quality of someone who had been sent for and did not enjoy being sent for. He listened to the music. He looked at the walls. He tapped things with his wand — he had a wand, which always slightly surprised students who had forgotten this fact — and the music persisted in the undisturbed way of something that had been anchored properly.
At the twenty-five minute mark it stopped. Not because Filch had done anything. Simply: the timing had run out.
The Defence class proceeded in the specific quality of a room containing thirty students who had decided that the nursery rhyme music had been the best use of twenty-five minutes of a Wednesday afternoon they could have hoped for and were keeping this assessment entirely off their faces.
He looked at the room with the attention he gave things he wanted to understand completely and thought: the music was in the wall from before the class started, which meant someone had been in this room before him and had placed it with the specific knowledge that the timing needed to run approximately through the middle of the lesson. The bows had required access to the portraits after hours. These were not idle jokes. These were crafted.
He thought about Fred and George, who had a certain relationship with timing mechanisms.
He thought about Fred and George's door on the third floor of the Wulfhall, behind which things had been built all summer.
He said nothing.
The third prank required more time to understand.
It arrived across Tuesday and Wednesday of the following week, and it operated in the specific way of things designed to produce a cumulative effect rather than a single incident. Every time Umbridge opened a door in the castle — classroom doors, office door, the door to the staff room — it emitted a sound. Not a loud sound. A small precise sound, about the volume of a politely cleared throat, that was recognisable after the first few instances as the specific ascending four-note phrase from Pop Goes the Weasel.
Not the full song. Just: pop.
The effect was precisely calibrated. It was not disruptive enough to report. It was not traceable to any wand work, because it had been worked into the hinges rather than the doors, which was a distinction that only mattered if you knew how the enchantment worked. It was entirely deniable. And it operated with the specific quality of something designed by people who understood that the correct tone for this kind of work was not contempt but a certain cheerful precision, which was more unsettling than contempt and considerably more difficult to address.
By Wednesday afternoon, Filch had inspected fourteen doors.
He found nothing. The sound continued.
It stopped on Thursday morning, at the same time as it had started the previous Tuesday, which meant the duration had been chosen as well as the delivery.
He went to Fred in the common room Thursday evening.
Fred was on the sofa with a parchment and a set of small brass timing mechanisms that he was adjusting with the focused care of someone doing something he found genuinely interesting. He looked up when Ron sat down beside him.
'The hinges,' Ron said.
Fred looked at him. His expression had the quality he used when he had decided the honest response was available. 'They're excellent for sustained sound enchantments,' he said. 'The resonance is better than you'd get from the wood. George worked out the duration mechanism in August.'
'The portraits were you as well,' Ron said.
'The portraits were Ginny,' Fred said. 'She did those herself. We did the music and the hinges.' He paused. 'And the thing with the teacup.'
Ron looked at him.
'She has a specific teacup she uses in the staff room,' Fred said. 'Monday afternoons. We arranged it so the tea pours pink for the first cup only. It corrects after that. We thought once was the right number.'
He sat with this for a moment.
'Is there more planned?' he said.
Fred considered this with the quality of someone assessing whether full disclosure was in their interests. 'Some,' he said.
'Don't escalate,' Ron said. 'What you've done is exactly right — it's small, it's untraceable, it costs her something specific without giving her anything to push back against. The moment you do something large, she has a target. Keep the scale.'
Fred looked at him. 'You're not telling us to stop.'
'No,' Ron said.
Fred nodded once, with the quality of someone who had received the input they needed and was filing it correctly. He went back to the timing mechanisms.
Ron went back to his reading.
The pranks continued through September and into October — small, precise, maintaining the scale he had specified and the register that was theirs: cheerful rather than cruel, crafted rather than impulsive, the specific quality of people who had decided this year required a particular kind of response and had thought carefully about what that response should look like. A jar of Fizzing Whizzbees that replaced itself in Umbridge's desk drawer every Monday morning, never traceable, always there. A brief recurring charm on her office door that made it stick for three seconds before opening — not long enough to be a malfunction, exactly long enough to be noticed. The portraits, which had gone back to normal but occasionally, without warning, waved when she passed them.
He documented none of it in the Witness records. It was not his operation.
It was, he thought, exactly right. You could resist something with confrontation and you could resist something with documentation and you could resist something with the specific persistent cheerfulness of people who refused to let the shape of the year be determined entirely by the thing they were resisting. Fred and George had found the third method and had applied it with the craft it deserved.
He looked at Umbridge across the Hall the following Monday morning and thought: you have been in a building that has been gently, persistently, and entirely untraceably making your life slightly worse since the second week of term, and you know it and cannot name it, and that specific quality of knowing-without-naming is itself a cost.
He returned to his breakfast.
Small things, properly placed.