The original novel mentioned plastic idols of Walt Disney's Mickey and Pluto, "the animal-headed gods of lost America" in the London History Museum. This film, being made by Universal, instead has plastic idols of Despicable Me (2010)'s Minions.
Author Philip Reeve, writer of the novel on which the movie is based, published a blog post on July 19th 2017 that principal photography had ended and he had been invited to the set back in May of the same year. He noted that he had been impressed by the actors and the sets, mentioning that "Most of it looked very much as I'd imagined, except for the bits which looked better."
When Hester's mother name is revealed to be Pandora Shaw, some viewers drew attention to the name of the software brand. This is actually a recurrent theme in the books, in which many characters have "ancient names" which are actually trademarks: Windolene Pye, Daz Gravy, Nutella Eisberg, Napster Varley, and Nabisco Shkin are all characters in the sequels. Others, like Chudleigh Pomeroy, are named after places in Devon, England, where author Philip Reeve lives.
Jackson purchased the rights to the book in 2009, but the film languished for several years before being officially announced in 2016. Jackson brought on several members of his production teams from the Lord of the Rings and Hobbit film series, and filming took place from April to July 2017 in New Zealand.
The book that Katherine Valentine brings into the Museum at the beginning of the film is written by one Nimrod Pennyroyal, a character that would have become important in the sequels.