‘They said I was disruptive. I wonder why?’ He paused at that point as though he anticipated an interruption. When that didn’t happen, he continued.

‘I was in and out of short-term sentences. Back then, there wasn’t any desire to educate inmates in Her Majesty’s prisons. It wasn’t until I had a substantial sentence that that became a possibility. I started with the O-level equivalents in English and Maths and went on from there.’

He paused and examined Magnus. ‘Can I ask you a question, Professor Pirie?’

Magnus nodded. ‘Certainly.’

‘Why are you so interested in sexual offenders and their thirst for knowledge?’

Magnus wasn’t sure he had a straight answer to that, so instead he said, ‘May I turn the question round and ask why the more intelligent prisoners tend to be in here for sexual offences?’

Alec gave a little snort of derision.

‘In my childhood, so-called sexual offences, just like domestic violence, weren’t regarded as crimes. According to the Bible, women were created for the pleasure of men, and children and wives were the property of their husbands. To do with as they wished.’ He smiled. ‘Maybe the sexual offenders in here just haven’t caught up with the changing nature of society.’

‘But that doesn’t explain why, in general, they are so keen on education,’ Magnus tried.

‘Most men in here are Neanderthal in nature and have one set of thoughts and actions they repeat ad infinitum. Also, they don’t favour the educational unit, but in some misguided sense of moral superiority, they dislike those who do.’

They spoke for another ten minutes or so about Alec’s choice of psychology at degree level. After which Magnus was left with the idea that Alec was viewing his subject specialization as a training ground in mind manipulation, rather than as a way of understanding human behaviour.

By then Archie had reappeared.

‘Time’s up, guys.’

At this, Old Alec rose more swiftly and easily than at the beginning of their meeting, leading Magnus to think that his earlier difficulty had been merely for show.

‘So glad to speak with you, Professor Pirie,’ he said, as though he were the interviewer and Magnus the interviewee. ‘Next time let’s discuss that Catholic orphanage and what was regarded as right and wrong in there.’

Archie ushered Magnus out, leaving Alec with his own guard.

‘So,’ Archie said as they crossed the open space between the halls, ‘what did you think of Old Alec as a fellow psychologist?’

‘He’s as intelligent and manipulative as you led me to believe,’ Magnus told him.

‘Don’t know if you’re into true crime podcasts and documentaries, Professor. But I watched an American documentary where a paedophile priest in charge of a girls’ school gets himself a certificate in psychology which he then uses to manipulate the girls even more than he did with religion. I can’t help but think Old Alec, who the guys in here call Secret Santa, has something similar in mind when he gets out of here.’