There was a sadness in Sally’s words. Jack thought she didn’t really want all these trappings of wealth; she was a much simpler soul than her husband. ‘Oh!’ Sally suddenly burst back into life as she took a sheet of paper from her pocket and handed it to Jack. ‘George said you’d need a list of staff.’

Jack speed-read the list: a housekeeper, a pool cleaner, three domestics, a tutor for Mathew, one full-time gardener and the seemingly ubiquitous Charlotte Miles who came three afternoons a week to deliver fresh fruit and veg as per Mathew’s strict dietary regime.

Jack thanked her and asked if Mathew normally stayed in the house by himself.

‘Rarely,’ Sally explained. ‘He was meant to attend the charity auction with us last night, but then he watched the episode where Ned Stark gets beheaded. He always watches the “death” episodes twice, which put him an hour behind and, well, we couldn’t wait for him as we were hosting. I started to keep track of where the “death” episodes were, so we could plan around them but there are so many! Have you watched Game of Thrones?’

‘People talk about it so much I sometimes feel like I have!’ Jack joked. ‘But no, I haven’t watched it.’

‘Mathew is . . .’ Sally faltered. At first Jack assumed she was going to open up about how hard he made life, but she did the exact opposite. ‘He’s wonderful. People think he’s to be pitied because he has an illness, but Mathew just is who he is and will be for the rest of his and my life. I love him without question, DS Warr, as you love your children, if you have any. Yes, there are rules, routines, dos and don’ts, behaviour charts and coping techniques that most parents don’t need to consider, but . . . it’s just horses for courses.’

Jack allowed Sally to continue telling him about Mathew, not because the details were important, but because her cooperation was. He needed her to like him, just as he’d needed Eloise Fullworth to like him, so that from this point forwards they were allies in his investigation. Sally spoke of how Mathew was not allowed a bank card, as his urge for instant gratification was too strong for him to control. And although he often experienced erratic mood swings, he’d rarely in his life been physically violent. Medication tended to keep him on an even keel.