Then Fry saw the car. It was a light colour, barely picked out by the streetlamps on the upper edge of the camera’s field of view. She peered closer, squinting at the boot and the rear wings.

‘Is that a Vauxhall?’

Murfin gave her a smug smile. ‘We’ve already blown up the screen shots and identified the model,’ he said.

‘Well done, Gavin.’

‘It gets better. The guys here read off a partial licence plate number for me, and I ran it through the PNC just before you arrived. We’ve narrowed it down to two possible owners.’

Fry felt her fists clench with excitement. It was the moment of breakthrough that sometimes came when you knew you were close to making an arrest.

‘Come on, Gavin. Don’t hold it back.’

‘It turns out that one of the possible owners of this vehicle works at Peak Mutual Insurance. A gentleman by the name of Ian Todd. He’s a colleague of Sandra Birley’s.’

‘Where does he live?’

‘In the Hathersage Road area – 28 Darton Street.’

‘Excellent.’

‘Darton Street isn’t inside the famous six-mile zone,’ said Murfin. ‘It’s way out.’

‘Yes, Gavin.’

‘So much for our profiler.’

‘She’s not a profiler,’ said Fry automatically.

‘So much for our special advisor, then. I guess her advice was just too special for me to cope with.’

As Cooper arrived at the crematorium, a hearse was creeping down the access road towards the chapel, followed by two black Daimler limousines, their gleaming paintwork streaked with raindrops. All three vehicles had personalized number plates starting with HS, indicating they belonged to Hudson and Slack.

Mourners who had already gathered under the porte-cochere to be out of the rain moved to one side to allow family members to disembark on the chapel side. By the time Cooper had parked and got out of his car, he could see Melvyn Hudson himself moving among the family, grey-haired and solemn, offering a few words of consolation.

At the side of the chapel, near the car park, was an area where the floral tributes from mourners were displayed. The day’s cremations were announced by a line of name cards on metal stakes, like place markers for an absent queue. Shirley Bramwell 10 a.m., Billy Booker 10.30 p.m., Lilian Outram 11 a.m. Each person’s slot in the schedule lasted half an hour. A cremation service was hardly an elaborate ritual, after all. It was more of a gesture, a quick farewell wave as the body passed through on its way to the flames.

Cooper noticed that the display of flowers included hearts and crosses, arrangements wired together to spell out ‘Dad’ or ‘Nan’, and a huge tribute in the shape of the Pearly Gates, with one of the gates invitingly cracked open an inch to welcome a new arrival to Heaven.