The room suddenly seemed airless, claustrophobic, and I had a powerful feeling of wanting to be somewhere – anywhere – else in the world at that moment.

Larssen said: ‘Burial of what?’

‘Burial as in shallow grave. Of human remains.’

‘With all due respect, detective, that seems incredibly presumptuous at this stage of the investigation.’

‘Does it? We’ve got the mobile phone data taking us there after our last known sighting of the victim. We’ve got the relationship between Mrs Lynch and Mr Delaney, blood on the seat of his burned-out car, we’ve got your client returning to the country park on Monday. We’ve got a six-foot patch of recently turned earth in the woods there, very near to the spot where your client emerged from the woods on Monday morning – muddy and out of breath. We have your client’s phone found at this secondary crime scene at the country park. And this afternoon the forensic team found a cigarette lighter at the scene with Mr Delaney’s DNA on it. Believe me, there’s nothing presumptuous about it.’

He let this sink in for a moment before asking his next question.

‘Tell me again, Joe. What words would you use to describe your encounter with Mr Delaney last Thursday?’

Larssen said: ‘No comment.’

‘When you left the car park on Thursday evening, he was unconscious, correct?’

‘No comment.’

‘Describe to me again what you did in the following two hours.’

Larssen gave me a small nod, so I ran through my movements as briefly as possible. The drive home, William’s asthma inhaler, the return to the car park. Home again, a bath for my son, dinner, washing-up, TV, bed.

Naylor addressed his next point directly at Larssen, opposite him at the small table.

‘Despite appearances to the contrary, I’m not giving you all this case-relevant material because I’m a warm and fluffy human being and I want to be your best friend, Peter. I’m telling you so that your client is absolutely clear about the weight of evidence we already have in the bag. So we can perhaps shorten this whole process and save a lot of time, legwork and heartache for the victim’s family. Bearing in mind we’re only just getting started on forensic searches of your client’s car, his computer and his house.’

‘We appreciate your candour,’ Larssen said.

‘In the light of the new evidence, is there anything else that you’d like to tell us?’

‘A minute alone with my client?’

‘Of course.’

Redford picked up the Dictaphone and said: ‘Interview suspended at 7.26 p.m.’

She hit a button on the machine and followed Naylor out of the room.

Larssen half turned in his chair and looked at me with an intensity I hadn’t seen before.

‘Well, Joe?’

‘Well what?’

‘They’ve been rather busy, haven’t they?’

‘Busy chasing the wrong man.’