Todd now had a team of friendly security people in high-vis jackets who gently explained this to unwelcome visitors. He seldom had to bundle people off the site himself. He still wore the Great Key on a chain around his neck every day. Keymaster was not just an honorary position. Walden had once had to explain this at length to a governors’ meeting. The Victorian thaumic engines in the great room adjacent to her suite looked very impressive and did a lot of work. But Chetwood had been here much longer than they had. The school’s ancient boundaries and gateways were part of a much older and subtler set of protections against magical danger, and the Key secured them. Shouldn’t it be given to a trained magician, then? she’d been asked. Or perhaps the Chief Marshal?

On paper, perhaps; but Todd had what he called a ‘knack’ and what Walden thought was probably a spectacular untrained talent for magic. She’d tried to suggest adult lessons, more than once, and the old man always just laughed. In any case, his nose for the fluctuations of magic around the school grounds was second to none. Several times now, he’d been the first person to alert Walden to a minor magical security issue before it could grow to a major one. In the 2003 incursion, more than twenty years ago, he’d been first on the scene, before any of the trained magicians on staff, before the Marshals.

Laura Kenning would probably want to know that, and talk to him about it. Walden put it out of her mind. She’d offered to sort out that session in the school archives. It could wait until then.

Todd was in a glum mood today. He’d been in the boiler sheds all afternoon. “Two years,” he said. “Two years of life left in those if we’re lucky. And the insulation’s gone to pot. Last time anyone looked at it was in the seventies, far as I can tell. Ten to one we’ll have to get an asbestos crew in.”

“I’m sorry, Todd,” said Walden.