I passed a small airfield, the runway lit up by orange lights, and then the dark swallowed everything again and all I could see were cat’s eyes, winking in the middle of the road, and a sign saying that it was three miles to the village the cottage was in.

The woman’s voice brought me back.

‘And this Zaid guy still thinks that it was Adrian Vale who killed Beatrix?’

‘He says he’s always believed that’s the most likely explanation.’

‘Does he ever talk to anyone else from back then?’

‘No. He says he kept in touch with a few of the other Politics students for a while after they graduated, but then they all started to drift apart, and now he doesn’t talk to any of them. Because of Zaid’s money, his net worth, the amount of cash he’s got plugged into these big companies – and, I suppose, the potential for him to be blackmailed and got at – he admitted he tries to keep a low profile. He never does interviews or profile pieces.’

Again, there was nothing suspicious about a very rich man choosing to limit his exposure to publicity, but the mention of blackmail made me wonder if this might actually be a lead worth chasing up. Pierce had got that money from somewhere, and there was no reason why it couldn’t have been from a man like Robert Zaid – a businessman, a diplomat, a government official, whose reputation and professional interests could be damaged severely over a mistake he might have made in the past: drugs, an affair, the wrong money to the wrong sort of people.

‘So, anyway,’ Patrick continued, ‘Zaid reckons that trying to keep himself out of the spotlight never helped very much when it came to staying in touch with the people he went to university with – but he also said that he felt Beatrix’s disappearance had begun to damage the friendships they all had, even before that.’

‘In what way?’