Chapter 23: Holmes Tells McGonagall Everything

The sky above the Astronomy Tower was beginning to consider the possibility of dawn — not committing to it, merely entertaining the idea — when Holmes knocked on the Headmistress's office door at four forty-seven in the morning.

He had his case-book under his arm, his coat was still on, and he smelled of basement stone and phenol derivatives and the particular cold that accumulates in rooms that have been sealed for longer than living memory. He had not slept. This was evident in the precise, slightly ferocious quality of his stillness as he waited on the threshold — the stillness of a man who has been running at full capacity for so long that stopping would be more dangerous than continuing.

McGonagall opened the door in her dressing gown, which was tartan and entirely dignified, and looked at him for a moment with the expression of a woman who had long ago made peace with the fact that crises do not observe office hours.