‘But it may be helpful if he has an unconscious supporting role. Essential that he doesn’t know it, of course. If he is in Brussels and if this is an EU intelligence operation, as we suspect – albeit an ad hoc one because they don’t have any operational intelligence capacity, as yet – then they’ll want to debrief him, won’t they? A renegade intelligence officer who has burned his boats and has nowhere to hide unless they find him a home and who is sympathetic to their cause – how could they resist debriefing him themselves, or at the very least doing it via Timber Wolf? It’s therefore essential that he and Timber Wolf do not give contradictory accounts.’

‘But that would mean you’d have to see him.’

‘It would.’

‘And Whitehall wouldn’t like you involving him.’

‘If they knew.’

They looked at each other in silence. ‘New territory for me,’ she said. ‘Too political, deceiving our masters.’

‘And for me.’

‘Not sure I believe that.’

Charles wasn’t sure he did, either, though he couldn’t remember contemplating anything quite like this before. It didn’t feel different from everyday espionage, merely like an extension of it. ‘If I could find him – big if – I’d have to convince him I’d come to persuade him to come back and resign honourably, nervous breakdown, medical retirement, that sort of thing. And in the process I’d let slip what I had already let slip to Timber Wolf. Then, when I’d failed to persuade him to come home – essential that I did fail – he and Timber Wolf would sing from the same hymn sheet to their EU masters.’

‘Mightn’t you be conniving with criminality?’

‘Maybe. Talking of which, any chance you could ask your helpful contacts whether the names Daniel Adamson or Abdul Salaam Adamson come up on any of their travel lists?’

‘Who are they?’

‘He is Sarah’s Muslim convert godson who’s gone missing. He’s wanted by the police, though as far as we know he hasn’t actually done anything except buy a few knives and have friends they’re worried about. MI5 know all about it. That’s how we come to be involved.’

‘He’ll already be on stop lists, presumably, which means there’s nothing more we can do.’ She smiled. ‘Even if I were to sully my professional hands with a sordid private initiative.’

‘I had a message from the DG about him only this morning. We’ve been reporting on him to MI5 but we’ve no idea – certainly no influence over – what’s going on at working level. It’s making life very awkward for Sarah. She’s probably with his wife now.’

Sonia stood. ‘I’ll let you know if I pick up anything.’