Warning: Spoilers for the second book of the Grisha trilogy, Seige and Storm.
Despite potentially spoiling it in recent casting announcements, Netflix's Shadow and Bone season 2 can still successfully pull off a major twist from the books. The first season of the series based on the Grisha trilogy books written by Leigh Bardugo featured a few surprising revelations. However, no twist was bigger (if not necessarily surprising) than the Shadow and Bone season 1 reveal that Ben Barnes' General Kirigan, a.k.a. the Darkling, was actually Aleksander Morozova, the Black Heretic who had created the Shadow Fold hundreds of years ago.
One of the biggest character twists from the books, arguably equal to the reveal that the Darkling is, in fact, the Black Heretic, comes in the middle book of the Shadow and Bone series, Siege and Storm. Early in the book, and likely in Shadow and Bone season 2, Alina and Mal become allies with a character named Sturmhond, an eccentric privateer with a gift for mechanical invention. He's clever, dangerous, and has seemingly been hired by the Darkling to find the sea whip, the second Grisha amplifier, and keep Alina and Mal under control. But he double-crosses the Darkling, having clearly had a secret plan all along, and soon reveals he's actually Nikolai Lantsov, the wayward youngest prince of Ravka.
It's hard to keep all of that secret, and Shadow and Bone season 2 has a challenge ahead of it to keep it from being spoiled for the people who have not yet read the books. But, thanks to Nikolai's double life in the books, the Netflix series has a built-in trick that will enable it to pull off his character twist without ruining it in the marketing. Nikolai goes through great lengths to disguise his identity when playing the role of Sturmhond. For starters, he doesn't want the target on his back of being Ravka's prince, but more importantly, he doesn't want anyone to treat him differently when they meet him. Thus, he has his face Tailored to change his appearance, turning his famous golden mop of hair and blue eyes to a reddish color and muddy green, as well as changing the shape of his face and nose.
Because of this, Shadow and Bone can pull off the book twist in the show without having to worry about spoiling it for non-readers in any of the marketing leading up to the show. People who have read the books already know the twist is coming, and those who haven't won't realize Sturmhond is Patrick Gibson, the same actor recently cast as Nikolai Lantsov. In the book, Alina notes to herself that something seems to be off about Sturmhond's face but she can't put her finger on it, and she's absolutely shocked when he reveals himself to be Ravka's prodigal son. Clearly, Shadow and Bone season 2 is counting on the same misdirection to fool its audience.
That's not the only character identity reveal potentially in store for Shadow and Bone season 2. The Grisha trilogy, as well as the Crows' duology (Six of Crows/Crooked Kingdom) has a number of surprising revelations in its pages. The most impactful reveals have to do with character identity; numerous characters in the Shadow and Bone books aren't who they appear to be at first, or go by assumed names and their secret identities turn out to be incredibly significant. The Netflix show can't use the same trick to obfuscate the truth every time and it will have to start getting clever with how it handles these reveals. However Shadow and Bone handles his reveal, Nikolai Lantsov is one of the most beloved characters from the books. It will be incredibly fun to see the smooth-talking, genius, inventor prince come to life.