‘Here,’ Conway said, nodding at a door. ‘Put your game face on.’ And pushed the door open.

A curly blonde turned around from a filing cabinet, hitting the big-smile button, but Conway said, ‘Howya,’ and kept walking, past her and through the inner door. She closed it behind us.

Quiet, in there. Thick carpet. The room had been done up with plenty of time and money, to look like someone’s old-fashioned study: antique desk with green leather on top, full bookshelves everywhere, heavy-framed oil painting of a nun who was no oil painting. Only the fancy executive chair and the sleek laptop said office.

The woman behind the desk put down a pen and stood up. ‘Detective Conway,’ she said. ‘We’ve been expecting you.’

‘No flies on you,’ Conway said, tapping her temple. She picked up two straight chairs from against a wall, spun them both to the desk and sat down. ‘Nice to be back.’

The woman ignored that. ‘And this is . . . ?’

‘Detective Stephen Moran,’ I said.

‘Ah,’ said the woman. ‘I believe you spoke to the school secretary earlier today.’

‘That was me.’

‘Thank you for keeping us informed. Miss Eileen McKenna. Headmistress.’ She didn’t put out her hand, so I didn’t either.

‘Sometimes we like to bring in a fresh pair of eyes,’ Conway said. Her accent had got rougher. ‘A specialist. Yeah?’

Miss McKenna raised her eyebrows, but when no one gave her more, she didn’t ask. Sat down again – I waited to sit till she had – and folded her hands on the green leather. ‘And what can I do for you?’

Big woman, Miss Eileen McKenna. Not fat, just big, the way some women get in their fifties after years of being the boss: all out front, hoisted up high and solid, ready to sail through anything and not get wet. I could see her in a breaktime corridor, girls skittering away in front of her before they even knew she was coming. Lots of chin; lots of eyebrow. Iron hair and steely glasses. I don’t know women’s gear but I know quality, and the greeny tweed was quality; the pearls weren’t from Penney’s.

Conway said, ‘How’s the school getting on?’

Leaning back in her chair, legs sprawled, elbows out. Taking up as much of the office as she could. Prickly as fuck. History there, or just chemistry.

‘Very well. Thank you.’

‘Yeah? Seriously? ’Cause I remember you telling me the whole place was about to go . . .’ Nosedive move with her hand, long whistle. ‘All those years of tradition and whatever, down the tubes, if us plebs insisted on doing our jobs. Here was me feeling guilty. Nice to see it all turned out grand after all.’

Miss McKenna said – to me, leaving Conway out – ‘As I’m sure you can imagine, most parents were disturbed by the thought of letting their daughters stay in a school where a murder had been committed. The fact that the murderer remained uncaught didn’t improve matters.’