‘No, but I said I didn’t think he’d really been at the hotel at all… Anyway, I made a bit of a scene and the girl who’d spoken to Alison took me aside and tried to calm me down; she said they couldn’t give out information about people without a good reason, they had a policy, blah blah… you know. But just to stop me crying, in the end she told me that he had checked in on the evening of the sixth, and checked out on the morning of the eighth. He made a fuss about being given the wrong newspaper while he was checking out, that’s why she remembered. So he was definitely there. I even asked her a bit, you know, hysterically, how she knew it was him, and she described him to a T. I know what he looks like,’ she added, before Strike could ask. ‘I checked before I left; his picture’s on the Landry, May, Patterson website.’

‘You’re brilliant,’ said Strike, ‘and this is all bloody fishy. What did she tell you about Alison?’

‘That she arrived and asked to see him, but he wasn’t there. They confirmed that he was staying with them, though. And then she left.’

‘Very odd. She should have known he was at the conference; why didn’t she go there first?’

‘I don’t know.’

‘Did this helpful hotel employee say she’d seen him at any times other than check-in and check-out?’

‘No,’ said Robin. ‘But we know he went to the conference, don’t we? I checked that, remember?’

‘We know he signed in, and probably picked up a name tag. And then he drove back to Chelsea to see his sister, Lady Bristow. Why?’

‘Well… she was ill.’

‘Was she? She’d just had an operation that was supposed to cure her.’

‘A hysterectomy,’ said Robin. ‘I don’t imagine you’d feel wonderful after that.’

‘So we’ve got a man who doesn’t like his sister very much – I’ve had that from his own lips – who believes she’s just had a life-saving operation and knows she’s got two of her children in attendance. Why the urgency to see her?’

‘Well,’ said Robin, with less certainty, ‘I suppose… she’d just got out of hospital…’

‘Which he presumably knew was going to happen before he drove off to Oxford. So why not stay in town, visit her if he felt that strongly about it, and then head out to the afternoon session of the conference? Why drive fifty-odd miles, stay overnight in this plush prison, go to the conference, sign in and then double back to town?’

‘Maybe he got a call saying she was feeling bad, something like that? Maybe John Bristow rang him and asked him to come?’