‘Well, we’ve fed dark Capris into Wotan, and now we have fed in that voice. Your people are out interviewing everyone in the nuclear energy industry and they’re sending the tapes to us. We are converting them into prints, and feeding them into Wotan in the hope he can match one print up with the conversation you recorded between Whalley and his contact. There are over two hundred thousand people who work in the nuclear energy industry – I have their files – it will take you until well past 4 January to interview them all – you’ll be lucky if you get your man that way.’

‘I thought you didn’t believe in luck?’

He grinned. ‘Let’s just say I sometimes believe in miracles!’

‘What about McEliney’s fingerprints?’

‘Nothing more than what I told you last week: his record was clean, but his father has a long record of IRA involvements; he was arrested in connection with the Hilton bombing back in the mid seventies, but there wasn’t enough evidence to convict him.’

‘But it does make it pretty clear there’s an IRA involvement?’

‘Oh, certainly. The voice you cannot place – the speech boffins have analyzed that, and they say the man was almost certainly born and brought up in Ireland, and has spent at least twenty years in this country since then. His accent may have faded naturally – but he might have deliberately worked at losing it.’

‘Can’t you single out everyone with an Irish background?’

‘We have already done so, and we keep a special watch on them as their voice-prints come in. But if he’s hiding his Irish background, he’s almost certainly changed his name and his identity, and without knowing who the person is, it’s a near-on-impossible job to find one person out of two hundred thousand who has changed his identity. Of course, it could possibly be this person Patrick Cleary that McEliney spoke of. There is nothing to prove it, though, and even if we could prove it, I don’t think it would be of great help to us.’

‘Why not?’

‘Because I think that’s a false name too. We’ve checked on every P. Cleary in all the phone books in the British Isles, and all the ex-directory listings – every possible way the name could be spelt. We’ve singled out all the Patricks, and checked on them, and we haven’t been able to find any positive IRA links. All of them have been telephoned, and their voice-prints have been compared with your tape; negative. That leaves us with three possibilities: either he isn’t on the phone, or he’s using a pseudonym, or he doesn’t exist.’

‘Which do you think is the most likely?’

Arthur beamed smugly. ‘You know I don’t normally like to give opinions?’

‘I had noticed.’