‘Ok,’ he said. ‘There are eight billion people in this world. Many more billions have lived and died here. Every single one of those billions is different in some way. Different DNA, different geography, different language, different culture, different upbringing, different experiences. There are infinite possibilities therefore as to how each person will turn out. And really, while as psychologists or criminologists or sociologists we love to put each one of those people into brackets, into defined groups with defined characteristics, I’m just not sure that it can work in every single case.’

Jessica looked at him quizzically like she wasn’t quite sure of his point.

‘So you do think some people are just inherently bad right from the start, no matter what?’ she said.

‘I do.’

‘Do you know of anyone who you’d put into that bracket then?’

Grant thought again.

‘Dennis Nilsen, perhaps?’ Jessica prompted.

Grant raised an eyebrow. He was impressed with Jessica’s knowledge. Though he wasn’t sure ‘impressed’ was really the right reaction to a young student who took a fascination with serial killers.

Nilsen was one of the UK’s most infamous murderers, convicted in the 1980s of murdering six men, but believed to have killed many more. And he hadn’t just killed, but had performed rituals with the bodies. For days and weeks after death he bathed them, dressed them and did who knows what else before eventually dissecting them and disposing of the remains.

‘Apparently,’ Jessica said, ‘in one of the interviews after he was arrested, when he was asked about why he’d murdered the men—’

‘He said, “I’m hoping you will tell me that”.’

Jessica smiled. ‘And he also spoke about how he felt no thrill or happiness in killing people. He wasn’t doing it for kicks. He simply felt compelled to murder. So don’t you think he fits the mould of a born killer?’

‘In many ways I’m absolutely sure he does,’ Grant said. ‘His crimes were abhorrent, and even he couldn’t justify them in any logical way. But, I think there were still triggers in his life that made him like that. I’m not sure he was born that way.’

‘Such as?’

‘Such as bereavement when his grandfather passed when he was a child. His closet homosexuality which, in that day and age, left him isolated and resentful. If you read his interviews with the police you can see how his sexuality severely damaged his ability to generate what we would consider normal and healthy relationships with others, both sexual and non-sexual.’

Jessica looked slightly disappointed again, not because she disagreed with Grant but because he’d so easily knocked back her suggestion.