Although ostensibly for children, the appeal of the novels is equally compelling for adults. Pullman's universe, like that of many other contemporary fantasy writers such as Michael Moorcock and Clive Barker, is multilayered and multifaceted, with possibilities for characters to slip between them. The Amber Spyglass won the 2002 Whitbread Book of the Year award, a prestigious British literature award. This is the first time that such an award has been bestowed on a book from their "children's literature" category.
The trilogy came third in the 2003 BBC Big Read, a poll of viewers' favourite books.
Warning: Spoilers follow
The novels draw heavily on gnostic ideas. The three major literary influences acknowledged by Pullman himself are the essay On the Marionette Theatre by Heinrich von Kleist; John Milton's Paradise Lost (which the title of the trilogy is taken from) and the works of William Blake.
Some have seen the series as a direct rebuttal of C.S. Lewis' Christianity-inspired Narnia series. Pullman has criticised in particular Lewis's use of a fictional cure for cancer in one of the Narnia books, which Pullman claimed would raise false hopes in children who were themselves, or who had friends or family members who were, seriously ill. He has also criticised the way Lewis excludes the character Susan from the final heaven scenes in The Last Battle, saying that she "goes to hell" for her growing worldliness and her rejection of Narnia. Lewis devotees argue that Pullman has read far too much into this; indeed Lewis made no such statement about Susan's final destiny, and never excluded the possibility of her rejoining her friends in heaven later.
A theatrical version of the books has been produced by Nicholas Hytner as a 6 hour (in two parts) performance at London's Royal National Theatre in Q1 of 2004. All 126 performances at the 1110 seater Olivier Theatre sold out before the opening day.
In the autumn of 2003, Pullman published Lyra's Oxford, which consists of a short story called "Lyra and the Birds," which focuses on Lyra at sixteen years old, and a collection of materials from all over the HDM universes, including a map of the Oxford of Lyra's world. Lyra's Oxford is a precursor to the forthcoming The Book of Dust, which, when published, will be a collection of short stories that focus on the trilogy's secondary characters.