Bastard Son & The Devil Himself makes "big changes" from Half Bad book

Back then, the plan was to turn the novel – which is set in a world where witches live amongst us and are divided into two rival factions – into a film.

"I wrote the screenplay but we couldn't get it made – as most films don't get made," Barton explained. "I slightly forgot about it and then it wasn't until just after [Barton's 2019 BBC/Netflix thriller] Giri/Haji had come out that The Imaginarium came back and asked if I'd be up for trying it for TV.

"They basically just took the first 60 pages of the feature script and and took that around town and used that to pitch."

Barton says the process of then getting a green light from Netflix was "really quick".

"I'd slightly sort of put it aside in my head, and then suddenly it was happening. So it was exciting – I had to get my head back into the world very quickly."

The protagonist of both the novel and the show is Nathan Byrne (played in the adaptation by Jay Lycurgo), a teenager who along with allies Gabriel (Emilien Vekemans) and Annalise (Nadia Parkes) embarks on a quest to find his father – a powerful and cruel witch.

Once the series adaptation was ordered, Barton said he "went back and did a load of rewriting on it", with the final product changing "a lot" from the movie script and also incorporating some "big changes" from the source material.

"It's a spiritual adaptation, really – it's the main three characters that are in the book and the world that Sally sets up, but in the book, Annalise isn't in it a huge amount. It's more Nathan and Gabriel that go on this journey and then she appears at the end – we wanted to bring her in and keep her in it more, because I always liked the idea of these three kids and their interactions and the complexities of their relationships.

"There's also stuff in the books that is great but we couldn't do – there's a whole section in Liverpool, for example," Barton continued. "Like with any adaptation, you change a bunch just to make it fit, unless you're doing Harry Potter or something where people just want the exact book on screen – this was more taking the characters and playing around with them a little bit."

Perfecting the first episode of The Bastard Son & The Devil Himself was "a really difficult task", according to Barton, since there's "so much backstory, so much lore" present in the book. "You're not just setting up a character, you're setting up the world and the rules of the world," he explained.

"We were in the edit room for, like, 21 weeks, which is the longest I've ever been in post-production on one episode. We ended up shooting additional stuff – we went in afterwards and added scenes. We wrote about 20 different versions of a prologue and epilogue, which we didn't end up using...

"It's difficult and we had, like, 100 different versions of [the first episode]. Luckily, we were given the time and the resources get it right, both in the scripting and in post-production, but it was really one of the hardest episodes to write. There was a lot of banging our heads against the wall and I was relieved when it was finished!"

One notable change from the book is the eye-catching new title for the Netflix series, which the production team landed on after considering "a long list of potential titles".

"We had some really terrible ones – like, 'Son of a Witch' and 'Bad Lad'," Barton laughed.

"[The final title] was on this massive list and the first time I looked at it, I thought it was too long and too weird, but it sort of stuck with us. It's a line of dialogue from the first episode, so that's how it got in there."

• The Bastard Son & The Devil Himself shares new look and release date

The Bastard Son & The Devil Himself launches 28th October on Netflix – sign up for Netflix from £6.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

Buy the Half Bad novel from Amazon now. For more to watch, check out our TV Guide or visit our dedicated Fantasy hub.

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