To his astonishment, he and Simon had been invited to Halliday’s home for this interview – though ‘required to attend’ would be a more accurate way to put it. He’d assumed Halliday meant her home in London when she’d first issued him with a visiting order; she and her husband Oliver had a flat in Farringdon, which, as far as Sellers had been aware, was their only home. No, there was another house in the country where Halliday was holed up working on an important project for a few days. That was where Sellers and Simon were talking to her now: in the kitchen of her white-painted, timber-framed farmhouse in the village of Brettenham in Suffolk.

Sellers hadn’t visited the kitchens of any other celebrity chefs, and he wondered if they were all so large. The canteen at the nick was bigger, but only just.

‘Yes, it’s distressing to be slandered, as you’d know if it had ever happened to you,’ Halliday snapped in response to Simon’s question. She was sitting across from the two detectives at the long table that took up a substantial part of the room and looked home-made – as if she and her husband had one day decided to chop down a tree in their garden, carve an uneven slice from it and stick it on legs. At one end of the table there was a pile of old copies of Lifeworld; at the other, nine bulging Sainsbury’s carrier bags that needed unpacking. The point of a cucumber protruded from one, a packet of bacon from another, the neck of a bottle of red wine from a third. A delivery man had turned up with the shopping five minutes after Simon and Sellers had arrived.

Halliday was wearing jeans and a black long-sleeved sweatshirt that was mercifully slogan-free. ‘You believe me about the books but not in general?’ she said to Simon. ‘Are you accusing me of lying about something? What?’

‘Billy. You’ve claimed he’s motivated by hatred of women. He isn’t.’

‘How do you know? Do you know who he is? No. You haven’t got a fucking clue! Of course, it’s much more fun to demonise me than to focus on your own shortcomings as detectives.’

‘I’ve got more than a clue,’ Simon told her.

‘That’s news to your friend DC Conkers. Look at him, poor startled goldfish. He wasn’t expecting you to say that.’

‘Why do you call him DC Conkers?’

‘Private joke.’ Halliday smiled. ‘Isn’t that right, Conkers?’

Sellers confirmed with a nod.

‘So you know who Billy is – well done! That’s great! And you’re not arresting him why?’

‘We’re on our way to making an arrest. There are other things that need to happen first.’