“Two cops; one killer; hundreds of gods.” So runs the tagline of Pagans, the debut novel by Penryn author James Alistair Henry, that imagines what life might had been like had 1066 or Christianity never happened.

An established TV scriptwriter, James’ CV ranges from comedy - Green Wing, Smack The Pony and Cornish radio sketch show Wosson Kernow – to children’s classics Bob the Builder and Hey Duggie.

A drily amusing murder-mystery, the world of Pagans is simultaneously distinct and yet somehow familiar. Themes of religious conflict, nationalism and prejudice are debated over takeaway coffees; crimes are solved with the help of databases and mobile phones. Characters exclaim: “Oh my gods!” and “What the hells?”

Britain is in political turmoil thanks to efforts to unite three separate peoples - the Celtic West, Saxon East and the powerful independent Nordic Kingdom of Scotland - into one country: a United Kingdom.

Amid this feverish atmosphere, a serial killer is on the loose in London, leading mismatched detectives Aedith, Saxon daughter of the powerful Earl Lod of Mercia, and quiet but canny Celt Drustan, to join forces in tracking down the killer and averting chaos in the capital.

Having spent his childhood in Falmouth, James moved to the south-east as a young man and was struck by the differences in character. “While most people assume north/south is the big cultural separation in the UK, I felt there was a real East/West divide,” he explains.

“I wanted to explore how the idea of cheerfully violent Saxon invaders driving the gentler Celts into the west 1,000 years ago feeds into cultural differences that remain centuries later.

“What do we take for granted in 'our’ UK that an inhabitant of Pagan London would be shocked by? How different would issues such as immigration, race and religion be if we were still a Pagan nation with hundreds of gods? And where would Britain fit on the world stage?”

James started Pagans during lockdown, when his TV work went quiet. “My wife Fiona had more work than she could handle so I looked after the kids, writing in the mornings while they were online home schooling.”

In return for the childcare, Fiona proofread his manuscript. “She did an MA in early medieval history and is now working on a PhD, so I could rely on her to tell me how different the Picts were from the Vikings.”

How did the novel differ from writing for TV? “I can write a sitcom pilot in a couple of weeks, or three sketches a day; In contrast, I was writing 500 words a morning, typing and sighing. It was a case of keep going until it’s finished.”

Pitched at fans of Game of Thrones and Terry Pratchett, Pagans has been optioned for a major Apple TV series. Will James write the script? “Maybe one episode, but I'll be creating a series bible to set the tone for others. I’m happy to focus on the books.”

That's “books” plural: James has plans for two sequels for Aedith and Drustan, so watch this space.