HBO/BBC's His Dark Materials is nearly halfway through its first season, and it's already spoiled several big twists from the books, but surprisingly enough this approach is actually working well for the series. Based on the fantasy trilogy by Phillip Pullman, His Dark Materials is making some fairly major changes to the original text. In the first two episodes, it was revealed that Mrs. Coulter (Ruth Wilson) is seemingly severed in this universe and that the Magisterium is a much larger and more ominous presence (and has outlawed Alethiometers), as well as a few other minor changes (combined characters, new scenes).
The biggest change, however, came in the second episode ('The Idea Of The North'), when Lord Boreal (Ariyon Bakare) stepped through a patch of air, and into a totally new world. In the original book series, Will's World (as this comes to be known) does not make an appearance until the beginning of the second novel - and the fact that Boreal is able to wander between the two as he likes is a massive spoiler that was casually dropped into the show. Now, in 'The Spies', another massive spoiler from the book has been laid out: that John Parry (Andrew Scott) and Stanislaus Grumman are the same man.
In 'The Spies', Boreal is back in Will's world, searching for Grumman, and has a little help from a hacker. In one scene, Grumman's entire history is laid out; that his name is John Parry, that he gained an Osprey as a daemon when he crossed worlds, that he has a son named Will, and that Will's mother has mental health issues. His history and the reason that he was in the Arctic are also laid out here. In the books, this takes nearly the entire first two books to be fully discovered - especially that Grumman is Will's father, so it was a shock to book fans to see it explained so quickly in the show.
However, despite revealing two of the biggest twists in the books right off the bat, His Dark Materials is actually making smart choices with how it is interpreting the original series. Rather than being concerned with following each plot point as it appears in the novels, the series has considered what is truly important to the trilogy as a whole, and is focused on the heart of the books, not the point-by-point story. This is why some of the smaller scenes and characters have been cut, and why the concept of multiple worlds is introduced straight away. It is also why Mrs. Coulter and the Magisterium are being set up as villains from the get go: the 'His Dark Materials' book series is about a battle between Church and free thought, among other things, and this show is making sure that new fans know that this is the good vs bad they can expect for the rest of the show.
The book changes actually mean that the series is more accessible. Rather than working through dozens of smaller twists and reveals, the audience is able to get straight to the heart of the matter, and enjoy seeing the tension rise between Lyra (Dafne Keen) and the Magisterium. The twists that are being spoiled are also not twists that are vital to the rest of the story. The audience knowing that the other world exists will not dampen Lyra's shock at finding out, nor will the audience (and Boreal) knowing that Grumman is Will's father change the emotional impact of the moment that Will finds out. In fact, this may even enhance it, as the audience will be rooting for that curtain to be drawn back for the characters. By allowing the viewer to know what the characters don't, it becomes easier to follow and to become immersed in, while preserving enough character surprise (and plenty more book twists to come) to keep these reveals important.
His Dark Materials continues with "Armour" November 25th on BBC and HBO.