‘Have you heard anything more about Erica Whiddon?’ he asked, rushing on before Casey could get out a word. ‘I’ve decided to resign from the Foreign Office, I thought you should know. Time to do something else. I’ll find something. The FCO has been in touch about . . . Well. They’re not thrilled. But they didn’t threaten anything. And if I’m leaving anyway . . . I don’t know . . . I hope . . .’

‘I haven’t heard anything else about Erica.’ Casey tried to sound reassuring. ‘I will let you know as soon as I find out anything. But Gabriel, there’s something else . . . When those MPs came out to Washington, do you know who organised it all? I think the trip was funded by a company called Chrysos Finance. Can you remember if they were involved in the planning?’

‘Chrysos,’ Bantham said hesitatingly. ‘I don’t remember . . .’

He paused, thinking. ‘There was a blonde woman who travelled out with the MPs. She seemed to be organising them. Knew about hotels, pick-ups, that sort of thing.’

‘What did she look like?’

‘Elegant,’ Bantham was definite. ‘Blonde hair, smart suits. Good legs,’ he excused the comment with a half-laugh. ‘Well, you did ask.’

‘None of them mentioned Chrysos at all?’ she said. ‘While they were out there?’

‘I don’t think so.’ Casey could imagine Bantham furrowing his brow as he spoke. ‘They were just enjoying the jaunt.’

‘Did they end up meeting the African president?’ asked Casey.

‘They did,’ Bantham said slowly. ‘At the Washington Ballet. There was a cocktail party. Several of the MPs went.’

‘Including Alicia Dalgleish?’

‘Yes,’ Bantham said confidently. ‘She definitely went along. She told me how much she enjoyed the ballet.’

‘And did the blonde woman go too?’

‘Yes,’ Bantham said. ‘She seemed to be good friends with Alicia. Chummy.’

‘Did you think’ – Casey made the question sound casual – ‘that the blonde woman might have had anything to do with Tartarus Energy?’

‘Tartarus . . .’ Bantham did the calculation fast. ‘Christ. No. I don’t think . . .’

‘Tartarus was never mentioned?’ asked Casey.

‘No,’ said Bantham. ‘I don’t . . .’

‘How did the MPs come to be going to the Washington Ballet? Who organised it?’

‘I can’t remember,’ Bantham said after a pause. ‘It was the MPs themselves who had made those plans. It wasn’t the embassy who sorted that visit . . .’

‘Do you think that Alicia might have been involved in planning that meeting? Or this blonde woman?’

‘She could well have been,’ said Bantham. ‘You think that Chrysos is linked to Tartarus?’

‘It might be.’

‘What does it mean, anyway? Chrysos?’

‘Chrysos’ – Casey felt her mouth stretch into a wry smile – ‘is the spirit of gold.’

‘So that would mean,’ Bantham worked it out, ‘that Chrysos funded the MPs’ trip, so they could lobby for its sister company while they were in DC?’

‘Something like that,’ said Casey. ‘Something like that.’