In an urban fantasy novel by one Darren O’Shaughnessy, Orion’s Simon Spanton—the book’s first editor—appears as a corpse and has his extracted guts used as a divining tool to predict the future stock market performance of his company.

Gruesome? Gory? Unsurprising when you realise this is the work of Darren Shan, who in his million-selling, 19-strong range of books for children variously dismembers families, dives into a world of guts and splatters characters with vomit. Procession of the Dead (Harper Voyager, March) is his first novel for adults, originally published by Orion in 1999 as Ayuamarca and now reworked and repackaged under the name D B Shan.

Shan makes a naughty schoolboy chuckle when Spanton’s name arises. “In my children’s books I often kill off people I know—loads of my friends get torn to pieces,” he says, reclining on a smart leather couch in his London crash pad (home is Limerick in Ireland).

“It’s a mark of respect—I never kill off anyone I don’t like, so I thought it would be nice to go back, put Simon in there and kill him off.” His publicist Helen Johnstone, he adds, will probably be killed off at some stage.

The addition of Spanton is not the only change Shan has made to the original novel. Written when he was 21, it was the first book he ever had published, and it sold only “a couple of thousand” copies despite positive reviews. Apart from changing the name of the book (“no one could actually pronounce it”), he has cut it back by around 100 pages and filtered in elements of the modern world to bring it up to date.

“I never felt that it was finished before,” he says. “I didn’t change the structure very much, as I didn’t want to go back and rewrite it completely. I just cut out things that didn’t need to be there. Back then, in my mid to late 20s, I was learning to express myself, I was saying more than I needed to say. These days I write more than I need and edit down, edit down, edit down.”

The cuts really show. Procession of the Dead rattles along at a breakneck pace, following the story of wannabe gangster Capac Raimi as he learns about life in the City, crosses paths with the all-powerful Cardinal, delves into the mysteries of the Incan priests who control more than meets the eye—and slowly comes to realise that he has entirely forgotten his own past. Shan describes it as a cross between “The Godfather” and the Coen Brothers.

Procession of the Dead is published under the name D B Shan to avoid alienating Shan’s large fanbase, but also to prevent his younger readers from picking it up. “One of the interesting things about this book will be how many readers follow across,” he says. “I don’t want 11–12-year-olds but I do want 14–15-year-olds to . . .”—he thinks for a second—“to follow me down the road of utter darkness.”

Gore and moralityShan always knew he wanted to be a writer, and after finishing an English and sociology degree at Roehampton University, he wrote while working for a television cable company in Limerick for two years, before quitting to see if he could make his dreams come true.

“I knew there was a good chance I might not get published, and I was drawing the dole for two years, but it was what I wanted to do.” First written was Ayuamarca, then the idea for his first children’s book, Cirque du Freak, arrived fully formed in Shan’s head. His agent Christopher Little loved it but initially struggled to sell it, as publishers thought it was too dark. HarperCollins took a chance—and eight years later sales through BookScan of Darren Shan’s books total 1.8 million.

Shan is still surprised there has not been more outcry about the gore, but says that despite the blood and guts, the books are actually very moral. “In Lord Loss, in chapter two a kid walks in and his family has been torn apart by demons: his dad is hanging upside down with his head chopped off, his mum is cut in two with a demon behind her moving her around like a puppet. It’s a really gory scene that I thought would get the book banned everywhere. But what it’s about is a kid dealing with loss, losing his parents. Good fantasy, especially for children, is about real life. It gets children to reflect on these things. Kids don’t want lessons, they don’t want to be told what to do if their mother dies in a car accident—snore—but reading an adventure book, they get close to the character, and if the character loses someone, they think about it.”

Shan works a few years in advance, so is currently up to 2012 in terms of his children’s books and 2010 for his adult titles; sequels Hell’s Horizon and City of Snakes will follow Procession of the Dead in 2009 and 2010. He’s keen to write more adult books, and the ideas are lining up thick and fast. “The trouble I’ve always had is getting the publisher to release the books quickly enough. I’d written up to book nine [in The Saga of Darren Shan] by the time they published Cirque du Freak.”

He spends around two years writing each book and has four titles on the go at once, doing eight drafts of each book. Working with long series means he can go back and sow the seeds for a future event if he desires: “If I come up with an idea in book seven, I can go back and put a hint about what’s to come in book two,” he says. “It’s quite a chaotic way of writing—like juggling—but it’s just the way my mind works.

“When I do my first draft in my head, I’m thinking everything’s brilliant—this is going to be Ulysses for the 21st century. Then I leave it for a year, and because I’ve put it aside for so long I can say ‘rubbish, rubbish, rubbish’. When you’re writing a book, you’ve got to get beyond that precious stage, and see it as the reader’s seeing it.”