‘My goodness, nobody in the family. Fortunately.’

‘We do have to ask you,’ Claire said. ‘Where exactly you were early on the Sunday morning when Mrs Roy was killed?’

‘In bed with my girlfriend, Victoria, at her house.’ He gave an address in Surrey.

‘She would substantiate this, I presume?’ she continued.

‘I certainly hope so.’ He laughed.

‘Did you like Mrs Roy?’ Gillard asked.

‘I respected her and everything she had achieved. But it’s hard to actually like a woman who fundamentally distrusts you.’

‘Because of the divorce?’ Claire asked.

‘Mainly. Compounded by the tissue of lies that my ex-wife told about me.’

‘You expected to head the business after Dr Roy’s death, we understand.’

‘When I married his daughter Dr Roy promised me I would become chief executive. So yes. But in the event, I must concede, Mrs Roy did do a splendid job. As I say, I respected her.’

‘But you didn’t like working under her?’ Claire asked.

He gave an exasperated sigh. ‘Well, obviously it grated a bit. She was arrogant and obtuse and sometimes got things wrong. But then, that can also be said of all of us from time to time, can it not?’

The interview over, Deepak Tripathi exhaled mightily, closed down the laptop and rubbed his hands over his face. The blank hotel room, its anodyne off-white bedspread and matching beige walls, seemed to him like a cell. He had lied to Philippa Boswell, and not for the first time. He wasn’t in Glasgow, but in the Orion Hotel at Heathrow Airport. He would have preferred to be in Glasgow, as far away from the police as possible, but he had business to conclude here, close to London.

He walked into the bathroom and rifled through his sponge bag for some tablets to deal with the stress. As he stared at his guilt-ridden face in the mirror, his mobile rang. He looked at the number and nodded to himself. This was a call he had been expecting.

‘Hello darling. No, it wasn’t too bad,’ he said. ‘They didn’t ask anything about that.’ He paused. ‘Look, I do need you to give me an alibi. Just say I was staying with you on that morning. Until at least nine o’clock I would have thought.’ He paused again as he listened. ‘I’m perfectly aware of that, it just saves complications. I need them off my back, for at least the next week. Then we can go away.’

He laughed. ‘Yes, somewhere like that, with no extradition treaty. Another couple of hours. Yes, back about nine p.m. I love you too. Bye.’

He hung up, and stroked his chin. Looked at his watch, then at his phone. He scrolled through his contacts until he found the one he wanted, a mobile number stored under a misleading name. He tapped it and waited for it to dial out. When the call was answered he said: ‘Is Xanthia available now? Good. Ninety minutes I think. I’m at the Orion Hotel, Heathrow, room 216. Yes, the usual. Stilettos, lingerie, that kind of thing.’ When prompted he read out his credit card number. ‘In half an hour? That’s fine.’