Shooting will begin on the six-episode series in Scotland later this year.
The commission comes a month after it was confirmed that a second series of Gaiman's Good Omens would also be filmed in Scotland for Amazon and the BBC. Henry has also recently joined the cast of Amazon's television adaptation of The Lord Of The Rings.
Anansi Boys follows Charlie "Fat Charlie" Nancy, a young man who is used to being embarrassed by his estranged father, Mr Nancy. But when his father dies, Charlie discovers that his father was Anansi: trickster god of stories. And he learns that he has a brother. Now his brother, Spider, is entering Charlie's life, determined to make it more interesting but also a lot more dangerous.
Published in 2005, Anansi Boys had developed in conversation between Gaiman and Henry and the comic read the audiobook. He also starred as Anansi/Mr Nancy in Radio 4's 2017 adaptation (pictured), alongside Game Of Thrones' Jacob Anderson and Green Wing's Julian Rhind-Tutt, having previously played Fat Charlie and Spider in a 2005 radio play version for the BBC World Service, co-starring Matt Lucas and Jocelyn Jee Esien.
Henry and Gaiman will executive produce the television series but it has yet to be confirmed whether the comedian will act in the adaptation. The pair will write with Arvind Ethan David, Kara Smith and Racheal Ofori, with production taking place at First Stage Studios in Leith, just outside Edinburgh.
In 2014, it was reported that Red Production Company and Endor Productions were adapting Anansi Boys for the BBC but it was never made, though elements of the script were incorporated into the US television adaptation of Gaiman's novel American Gods, which stands alone, rather than as a prequel to Anansi Boys, despite Mr Nancy appearing in both books.
"Anansi Boys began around 1996, from a conversation I had with Lenny Henry about writing a story that was diverse and part of the culture that we both loved," Gaiman said. "I wrote a novel, an (I hope) joyous and funny book about a dead god and his two sons, about birds and ghosts and beasts and cops, based in Caribbean and African tales. It was my first number one NYT Bestseller, and went on to become a beloved and award winning book.
"Anansi Boys as a TV series has been a long time coming - I first started working with Endor and Red on making it over a decade ago," he added. "We needed Amazon Prime to come on board and embrace our vision, we needed a lead director with the craft and vision of Hanelle Culpepper, we needed the creative and technical wizardry of Douglas Mackinnon, who worked out how we could push the bounds of the possible to shoot a story set all over the world in a huge studio outside Edinburgh, and we needed the rest of the amazing talents that nobody knows about yet."
Henry added: "I've been a huge fan, and couch sleeping friend, of Neil Gaiman's for over 30 years, and I have loved being a part of the Anansi Boys' creative team. I love that we're going to have a suitably diverse cast and crew to tell this joyous story. What's great is that the whole production is listening and ensuring that inclusion is happening and is being seen to be done."
Henry is publishing his first children's book, The Boy With Wings, on 14th October, and Black British Lives Matter on 18th November with Marcus Ryder, a collection of essays on the Black British experience within the Black Lives Matter movement.
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