I am halfway past his door, when I see he has jumped up from his desk and is rushing towards me.

‘So terrible about your sister.’ He peers through unfashionable steel-rimmed spectacles, under a mop of reddish hair, his paunch struggling out of a faded stripy brown-and-white Viyella shirt. Just a few years older than me, he would be at home in a polytechnic common room. He typically prefaces everything he says with ‘Erm’, which weights his words with deliberateness. ‘Erm, I’m so sorry.’

‘Thank you,’ I say.

‘Erm, it must be hard for you.’

‘It’s OK. I’m bearing up.’

This is excruciating. Alan Scott is a legend at exposing financial scandal and complex public-sector corruption, his forensic investigative powers second to none. But although well meaning, he is shy. In Parliament’s bars, while the rest of us are deploying our papers’ expense accounts to buy round after round for the mob of biddable MPs, he’ll be persuading a junior civil servant to photocopy a valuable road-widening contract that proves a couple of million quid of public sector money is lining the pocket of a mate of the secretary of state. He’s like a terrier chasing a rat. Once he has the scent, he won’t stop until the scandal is exposed. Right now, I have a feeling his solicitude isn’t quite what it seems, because he is blocking my way and showing no signs of moving.

‘Alan, is there something on your mind?’

‘Erm . . .’ He hesitates, furrowing his brow. ‘Well, actually . . .’ Another pause. And then he blurts, ‘You don’t happen to know if she left anything for me?’

‘She . . . Who?’

‘Clare. Some papers, or maybe a floppy disk?’

‘I haven’t a clue, Alan. What on earth do you mean?’ This feels inappropriate. I know he’s gauche, but . . .

He already backing away. ‘Sorry, I shouldn’t have said anything. Dim of me. It’s not something you should be bothering yourself about now. Let’s have a chat in a few days.’

This is annoying. He can’t say that he has been in contact with my sister and then expect me to back off without knowing more. If Clare needed help from a journalist, why from him? Why not me?

I need your help.

Did she turn to him because she couldn’t get hold of me?

‘When did you speak to her?’

The urgency in my question stops his retreat. He sucks in his cheeks.

Too many painful thoughts are colliding. Nothing makes sense: neither that Clare broke the principled habits of a lifetime and ignored Civil Service rules against unauthorised contact with the press, nor that she chose to do so with this holier-than-thou prick.

‘Spit it out,’ I say. ‘Why was she in touch with you?’

He glances around, looking for an escape. ‘Gil. I don’t know what . . .’

‘Who do you think you are protecting?’ I interrupt. ‘Your source is in no position to complain.’