‘Not until I’ve seen that crashed car.’

She could see the set of his jaw. ‘Okay, Craig. We’ll go there first.’

She wouldn’t let him drive. Claire took Gillard’s unmarked Vauxhall, allowing her to blue-light it the eight miles to the country lane where the vehicles had been found. During the journey Gillard worked his phone, chasing every little detail of the unfolding incident. The first confirmation came quite quickly that it was Trish’s Ford Ranger that had been discovered, but it took arrival at the scene to take in the full horror of what had happened.

Such was the press of emergency service vehicles close to the little church of St Botolph’s in Banstead that Claire parked 200 yards away, intending to walk. But the moment they stopped Gillard jumped out and hurried up towards the blue crime tape, and the big blue SUV, doors open, just by the lychgate of the churchyard. White Tyvek-suited figures lit by powerful floodlights were busy inside. Bloodstains could be seen on the seat. Claire found her boss by an ambulance, where the crew were in the process of confirming to him that it was an elderly lady who had been inside the car and was now in hospital.

‘She’s sustained severe head injuries,’ one of the paramedics volunteered. ‘I’ve just been on the phone to intensive care. She’s in a coma, with a bleed on the brain. I’m sorry, but the registrar says the prognosis isn’t good.’

Claire took Gillard’s arm. He had no coat or jacket, no lanyard for ID, and was still dressed in his white shirt and dark work trousers, his tie askew. He looked ashen, as if in shock. But her attempts to restrain him were futile. He marched on towards his aunt’s vehicle, recognising one of the CSI technicians, Kirsty Mockett, the girlfriend of Research Intelligence Officer Rob Townsend.

Claire listened in as Kirsty described what seemed to be a savage attack against Gillard’s aunt. ‘I don’t think she stood a chance,’ Kirsty said.

‘Are there any eyewitnesses?’ Gillard asked.

‘Uniforms are doing door-to-door, but no houses look out just here,’ Kirsty said.

Gillard looked around, eyes swivelling crazily, as if there would be evidence ripe for the plucking if only he could spot it. ‘Look for tyre tracks for Sam’s car. She had Michelin radials, front left replaced just three months ago. Look out for her other earring, a tiny butterfly. She lost the first one in the house.’ He barked out another half-dozen pieces of forensic advice to the young CSI, who merely blinked.

‘Come on, Craig,’ Claire said, taking him gently by the arm. ‘Don’t try to do everybody’s job. We need you calm, well slept and focused tomorrow, because there are certain things that only you can tell us. For tonight, there is nothing more you can do.’

He nodded, accepting the advice.

‘I’m sorry about your aunt,’ Claire said. ‘I know you are no great fan of hers, to put it mildly, but she has put her life on the line to save Sam. That’s redemption, isn’t it?’