I was just at the part of the story where Lockwood settles down in his room at Wuthering Heights for the night, and a little hand comes in at the window and a voice pleads to be let in.

Lockwood was terrified, and desperate to shut out whatever it was, and he brought the window down so hard on that little hand that he drew blood. It was exactly as if it wasn’t a ghost at all, but a real girl, begging to be allowed to come out of the cold.

If it had been a traditional ghostly hand, a wisp of white that wasn’t really there, it wouldn’t have bothered me nearly so much. As it was, it made me feel sick.

I looked away from the book, past Ava to the window. No ghosts up here, and the windows couldn’t be opened anyway. Planes were never haunted, were they? Much too modern. You wanted an old house for that kind of thing. A place that was warped and crooked and badly maintained, with windows that didn’t shut easily and gaps where things could get in.

For a moment I saw it – just as you see the landscape below you when you’re flying and the clouds part.

There was something. Someone. Someone Mark didn’t want anything to do with, but couldn’t or hadn’t got rid of. Did he want to? Or did he want to hang on? I couldn’t tell.

And then the moment passed. Ava wasn’t about to talk to me and we had at least an hour left to go.

I went back to Wuthering Heights. There was a load of other stuff going on with Hareton and Heathcliff and all sorts of people who were nasty to each other and hard to keep track of, but that little ghost girl scratching at the glass didn’t turn up again, and for that I was grateful.

Predictably, the French official who checked our passports eyed Ava up – he tried not to be obvious about it, but I noticed it all the same. Honestly, men – they were like animals. Dogs with their tongues hanging out. When Ava was around, anyway, though she did her usual frosty thing of behaving like it was all beneath her.

I didn’t realise how warm it was till we stepped out of the airport. Then – whoosh! It was like being drenched. The air was so still and heavy, we might as well have been walking through hot water.

Ava slipped off her cardigan and walked on looking proud and indifferent, as if she was determined not to notice any attention people might pay her. It occurred to me that in some ways it would be a disadvantage to be so conspicuous. There was something to be said for being comparatively invisible, even though I often wished I wasn’t.

A series of wonderful surprises followed, which Ava pretended to take in her stride and Mum and I were thrilled by.

First there was the hire car, a long flashy sporty white thing and air-conditioned, so Ava got goosebumps and had to put her cardigan on again. Then there were the glimpses of the sea from the road – so blue, it was obviously far from home. And finally there was the Grand Hotel itself, with its name spelt out in gold above the glass revolving door, and pillars to either side and an attendant with a cap and braid on his uniform.