Anna reluctantly agreed with me. I could tell from the sulky expression on her face that she wanted to come too, but Jane had asked for me, and she respected that. When I asked Singh if he wanted to join me, he was clearly exasperated at me for going behind his back. He accepted the invitation to join me, though I could tell he would have some questions for me about why I hadn’t already told him about my planned visit.

The weather had improved since the beginning of the week, and I enjoyed the twenty-minute drive through the countryside. Jane Villiers lived on the edge of the Lincolnshire Wolds, the limestone ridge running roughly north to south through the northern half of the county.

Her house wasn’t the only picture-perfect one in the village, and I admired several as we drove through. I could imagine there was a lot of pressure on residents to maintain the same standards as their neighbours when it came to their homes and gardens. One house we passed was next to a ford, and I could see the stream winding under the fence and through the garden, complete with a little ornamental bridge. I thought it would be nice to come back in the summer, when all the gardens would be a riot of colour.

Jane was waiting for us and had opened the front door before we reached it. She frowned at Singh, then looked faintly amused when I introduced him.

‘I suppose I should have expected Paige to bring someone from the police with her,’ she told him. ‘You might have had a wasted trip, I’m afraid, Detective. I don’t know if my concerns are really worth listening to.’

Singh gave her one of his winning smiles. ‘I understand, but I might think of a couple of questions I’d like to ask you anyway.’

There was a pause, then Jane nodded, and led us into the front room again. I sat on the same worn sofa as before, while Singh stood and examined some of the pictures on the wall.

Jane came back in with tea and cake, and served us before sitting back and steepling her fingers, looking at us over the top of them.

‘Now you’re here, I feel almost foolish,’ she said with a sigh, rubbing the bridge of her nose. ‘I’ve been going over this in my mind repeatedly – could I have prevented this? Has this all stemmed from my failure to protect my students?’

Singh came and joined me on the sofa, resting his elbows on his knees as he looked at the ex-head teacher.

‘Why do you think that?’