Jack Thorne reveals how the Grenfell Tower fire shaped his Channel 4 drama The Accident

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"The idea was always to look at class and restorative justice, that that was the sort of thing that we wanted to look at, and I had an idea in my head," he said. "And then Grenfell happened, and the idea changed."

In the early hours of 14th June 2017, a fire broke out in a 24-storey block of flats in West London and spread upwards with terrifying speed – thanks to flammable exterior cladding on the tower. The official death toll stands at 71, including small children and whole families. The Grenfell Tower Inquiry is ongoing.

But in the aftermath of the tragedy, Thorne decided not to dramatise this story directly.

"I actually was offered Grenfell three times by three different production companies, who wanted to tell the Grenfell story," the screenwriter said. "And I didn't feel like there were the facts in place to look at it properly without hurting an awful lot of people, and doing a television thing of trampling over people's lives. Not to say that there isn't a beautiful drama to be made, I just didn't feel capable of it myself."

Instead, Thorne wrote a powerful and shocking drama set in the fictional small Welsh town of Glyngolau, where a large construction project offers hope of regeneration. It is the pet project of Councillor Iwan Bevan (husband of Sarah Lancashire's Polly) and is overseen by a property development company.

One day there is an explosion and – while locals look on in horror – a catastrophic collapse, which leaves many dead.

Grieving families look for answers and demand justice. But will they be able to hold the right people to account? Who is to blame?

"The concept of looking at corporate manslaughter, and the way that a corporate manslaughter trial might work, came about. And then we just researched like mad until we found a story that worked for that," Thorne explained.

On his response to Grenfell, he added: "This is extraordinary that this has happened in our country, when we're supposed to be people that are capable of looking after each other.

"And then this phrase 'corporate manslaughter' kept getting thrown around and I didn't understand it, and then it was looking into that and going, 'Okay, how does this work? And what is that, and what is the charge, and how does it stick?' – that was the starting point for the whole thing."

But as he soon found, legal repercussions for major catastrophes like this are few and far between.

"The more we looked into it, the more impossible it became bringing charges that stuck," he said. The Bradford City stadium fire, Hillsborough, Aberfan: "All these different tragedies and none of them have had successful... well, they've all had elements of successful things that have resulted from them, but no one has ended up in jail for what was clearly in some cases quite severe negligence."

And in the aftermath of Grenfell, Thorne points out how little progress has been made in removing that flammable exterior cladding from people's homes. Continued at the current rate, it could take until 2030 for these deadly materials to be removed from every tower block.

"When you look at the situation with Grenfell now, there are still 14 families that have yet to be found a home," he said. "Everyone was shouting about it for a little bit, but in our noisy culture then it all goes quiet. And these people that have had their lives devastated ,and these people that are still living in these flats are just terrified, and can't sell them and can't move out, or they're local authority flats and they can't be put anywhere else.

"And so it feels like television could tell a story which was not looking at Grenfell directly but by looking at another story around that, that maybe we could do a bit of light-shining."

He adds: "The idea that you can single someone out to blame is very, very tricky in all these cases. But at the same time, it's also very clear that the judicial system doesn't find a way of finding answers to that question... people do need justice, and also justice leads to things improving.

"The fact that this cladding is not being taken down is really, really crucial because it means that the companies that put the cladding up aren't frightened enough to remove it. And that means that [justice is] failing, because the only reason that we need the police is in order that future crimes aren't committed. Future crimes are still there. Future problems are still there and they haven't been removed, so that means that justice is failing."

For now, Thorne is waiting with bated breath until The Accident hits our screens.

"It's terrifying," he admitted. "And this one feels really terrifying, because you're aware you're writing about something that really, really, really matters."

The Accident will air on Channel 4 from Thursday 24th October at 9pm