‘What? Why didn’t you tell me? When was that?’

‘Couple of months ago? Her name was in the diary as Clare Prince. I didn’t make the connection until I saw her photo in the paper.’

‘Wait,’ I say. ‘Clare Prince? She always used her maiden name.’

‘It said “Prince” in the diary. I would have joined up the dots otherwise.’

In protecting Todd, Marilyn is scrupulous. She vets everyone. It seems odd that Clare would use her married name. Another thing I didn’t know about her.

‘Why did she see Todd? Was it a transition meeting?’

That would make sense. When an election is nearing, senior mandarins have ‘transition’ meetings with Opposition leaders, so that the civil service can do preparatory work in case there’s a change of government. It is all proper, part of how Whitehall tries to provide continuity in the run up to and aftermath of an election.

‘I wasn’t in the room.’ There’s an edge in her voice. Marilyn does not like to be kept out of anything. ‘No one was.’

This seems odder still. All her life Clare was a stickler. Private meetings between senior civil servants and Opposition MPs are not the norm, and in some circumstances would be a serious breach of propriety. ‘So did Johnny say what it was about?’

‘He was evasive. I thought maybe she wanted to get in with him. Chances are we’ll appoint a new Permanent Secretary at the Treasury after the election.’ She adds, as a superstitious rejoinder, ‘If we win.’

It’s true Clare was ambitious: she definitely wanted to be the first ever woman boss at HM Treasury. But she would also know that if it leaked she was cosying up to the leader of the Opposition, all bets would be off; she might even be sacked. Clare wasn’t that kind of risk-taker.

‘None of this sounds like Clare.’ I scratch the back of my neck. ‘But what do I know?’

Marilyn goes to her dresser. Behind bottles of Chanel and Lancôme, beads and hair clips, is a bottle of red wine, half-empty, cork wedged in. God knows how long it has been there. I am wondering whether she was sharing it with someone else in her bedroom. I banish the thought: I have no claim on Marilyn. There is no us.

She opens the bottle. ‘Drink?’

‘How long has it been there?’

‘A day. Two days, maybe.’ She takes a small swig. ‘It’s fine. Wait here.’ She disappears to the kitchen and comes back with two tumblers that don’t look quite clean.

I’m desperate for a drink, but I don’t trust the glasses. ‘Thanks. I’ll do without.’

Marilyn fills her own glass to the top, and sits on the hard-backed chair by the dresser. I sit up in the bed. ‘How come you never told me you had a high-flying sister at the Treasury?’

‘We sort of fell out.’