Bennet was tall enough to see this over the centre console. He shrugged. ‘It actually makes sense.’

But not to Nick. ‘So why are we here? Someone start explaining.’

Bennet looked at Miller, who was by the front of the car. Nick looked, too, but she said nothing, and a moment later she disappeared behind the bonnet as she raised it.

‘Tell me!’ Now he was almost dizzy with confusion. ‘I want to know what’s going on. Right now.’

Bennet reached across to slap a sheet of paper on to the passenger seat. ‘We got this from the DVLA.’ It was a certificate of destruction. He pointed at the Vehicle Identification Number. Nick looked down at a little metal plate near where the passenger seat was fixed to the floor. The VIN, stamped into the metal, matched the one listed on the certificate. No two cars had the same 17-character code. And the customer’s name was Anna Middleton, with her old London address. One Fiat Punto scrapped by the issuing establishment of Watson-Bruce Salvage. There was also a small sale receipt stapled to the certificate, and the registration number there matched. Sale of one 05 Fiat Punto from Anna Middleton to Watson-Bruce Salvage. It was Anna’s car. He was puzzled by the carpet. No bleach stain. Just the rat.

Bennet’s finger touched the date printed on the destruction certificate. Same as the sale receipt: 19th September 2011.

Nick said, ‘The date she scrapped it. So? Look, I’m getting a headache.’

Bennet reached out to him, a car key on a card tag dangling from his fingers. Nick took it. He recognised it. In handwriting the tag simply listed make and model, and a tiny printed number: 1051.

Bennet said, ‘These key tags are from a book. Sheets of them, serrated, and each tag is numbered, so you tear them off in order. This is the one after.’

Bennet held out another key, which Nick took. This tag listed make and model, but also registration, and the date. A Renault Mégane, 2003, tag number 1052.

But the date was 12th September 2011.

‘You’re saying Anna sold her car before the 12th? You’re saying she sold it on that first occasion when she came down? No, she drove it back. She had it another week or so. The damn police came to look at it, remember.’

‘And you spilled a bottle of turps in it,’ Bennet said.