I break off as the cellar is suddenly flooded with daylight: Harper must have been able to open the hatch from her side. She’s talking to me, but I’m still trying to adjust to the searing brightness blinding me after so long in the dark. I feel nauseous, and fight back the urge to vomit. I think I’m about to pass out.

‘Mummy,’ Peter says, tugging at me. ‘Mummy, help me up! I can climb out! I can show Harper how to open the cellar door!’

The light is briefly blocked by Harper as she peers in. ‘Can you fit through, Peter?’

‘I think so.’

Through sheer willpower, I hoist my son up towards the hatch again. It’s a tight squeeze, and for a moment I think he’s not going to make it.

But then, suddenly, miraculously, he’s free.

‘Call the police, Harper!’ I shout. ‘Don’t go into the house alone!’

‘I’m coming!’ she calls. ‘Just hold on, Millie! I’m going to get you out of—’

And then abruptly she’s gone.

SETtalks | psychologies series

Science ♦ Entertainment ♦ Technology

Inside the mind of a psychopath | Original Air Date 9 July

The transcript below has been lightly edited for length and clarity.

You all know the story of what happened at the Glass House: the horror of what took place in that cellar. You’ve watched the news and read the papers and seen the documentaries.

In the annals of crime, it’s not the worst. It wouldn’t even make it into the top ten. But there’s something about the Glass House Murders that keeps the story on the front pages anyway. You just can’t get enough of it, can you?

Maybe it’s because it all started over the purchase of a house.

Ridiculous, isn’t it? I mean, we all know about property feeding frenzies, but this takes gazumping to new heights.

I think it’s because it has such a great cast of characters. It’s got made-for-TV written all over it, doesn’t it? A famous television presenter who claimed she locked her abusive husband in the cellar for five weeks at his instigation as part of a complicated Ponzi fraud. A brilliant heart surgeon who cut off her own hand to save her son from being frozen alive in a chest freezer. A popular vlogger who stirred up a hornet’s nest and then jumped right into the middle of it.

And at the centre of it all, there’s the Glass House. It’s a character in its own right, like Downton Abbey or Manderley. The kind of dream home we’d all kill to own.

It’s no wonder you’re obsessed with the story. I don’t hold it against you. You should know by now I’ll never judge you. You can show me your darkest selves and I won’t look away.