How 'The Expanse' Season 4 Compares To The Book It's Based On

Fans of the television series The Expanse likely know that the show is based on the books written by James S. A. Corey, the pen name of co-authors Ty Frank and Daniel Abraham. Each season roughly follows the story from one of the books, and Season 4 is no different; the main plot of the show taken from Cibola Burn, the fourth book in what's expected to be a nine-volume book series (the eighth book, Tiamat's Wrath, was published this year, and the final book is expected to come out in 2020). Like most television adaptations, there are necessary differences between the source material and what we see on screen. The Expanse is no different in this regard, and there's a lot pulled in and taken out from the books in season 4. "At the end of a season, [co-authors Ty Frank and Daniel Abraham] and I will start talking about the plan for the next year," showrunner Naren Shankar told /Film. "I will often have my feelings about how we should adapt it, what changes we should make, but the three of us talk about those things." Read on to learn about some of the differences these three creative minds agreed upon for the show, including Shankar's perspective on why some of them were made.Warning: heavy spoilers below for both Season 4 of the television series as well as the fourth Expanse book, Cibola Burn. There's also very light spoilers for the fifth Expanse book, Nemesis Games. 

One of the main points of view in Cibola Burn is from Havelock, Miller's old partner when they were both detectives on Ceres. By the fourth book, Havelock is now working security for the UN-backed corporation sent to establish a presence on New Terra (AKA Ilus). Unlike his boss Murtry, however, Havelock stays on the Edward Israel for the entirety of the book, where a bunch of "deputized" engineers get all Lord of the Flies with a grudge toward Belters. This whole storyline, including Havelock changing sides and eventually making it to the Rocinante, is completely left out of the fourth season. This omission, however, is a reasonable one—the theme of civilized people becoming less-than civilized is well covered by Murtry on Ilus, and by keeping this storyline out, the show was able to build out Bobbie, Avasarala and the OPA storylines, which are barely present, if at all, in the book. 

With the exception of a few choice messages to Holden from Avasarala, the entirety of Cibola Burn takes place on Ilus. If the show followed this trend, that meant that fan-favorite characters Bobbie, Avasarala, Ashford and Drummer wouldn't make an appearance in Season 4 at all. Fortunately, the show did include storylines for all of them, and even pulled from the source material, both from the fifth book, Nemesis Games, and also from one of the The Expanse novellas that James S. A. Corey have also published. "A lot of Bobbie's story is from the novella Gods of Risk," Shankar explained in an interview with /Film. "We thought it was a really interesting way to finally go to Mars. We wanted to see what that place was—we'd touched on it by going there on ships and seeing what Martian culture was like, but it was always effectively on a naval ship, so it gave us a chance to go into that world and what life is like there." Avasarala's election threat isn't touched on at all in Cibola Burn, though it gave the show a chance to not only touch on how the discovery of the ring gate affected Earth, but also to provide a deeper look into Avasarala's relationship with her husband, and how something as intense and stressful as a global election can strain even the strongest relationship. And then there's the OPA. Marco Inaros, the Belter with a grand violent vision to kill a lot of Earthers, is a character that was pulled from the fifth book into the fourth season. Without getting into spoilers for Nemesis Games, seeding Marco's character this season effectively tees up the likely major conflict for Season 5. Introducing Marco now also helped emphasize the internal struggles the OPA is facing in trying to legitimize itself to Earth and Mars. 

In the book, Naomi never even tries to acclimate to high-gravity life on Ilus; her time in Cibola Burn is spent on the Rocinante and as a prisoner on the Edward Israel when she tries to disarm their armed shuttle and gets caught. In Season 4, however, Naomi desperately wants to be able to live planet-side. Dominique Tipper, the actor who plays Naomi, explained to /Film what motivated her character to do so: "For her, the want to be on a planet and experience what's that like is partly her own curiosity, and partly the hope of relieving some of the Belters' plight and their reliance on Earth. I think for her, this is a good solution, because for Naomi, you're never going to catch her going to Earth—that's her oppressor's planet. Now that the ring gates are open, for her that's an opportunity to exist there with the man she loves. And so they get the best of both worlds. You get to see her go through this really difficult journey to try to get her body to adapt to atmosphere, and it's a real struggle for her."Naomi's struggle to stay planet-side ultimately fails, which brings with it not only a poignant moment for her and Holden, but also hammers home the larger point that there will be Belters who won't be able to settle on any of the new planets. What will become of those who have to stay in a low-gravity environment? The OPA, including Marco, are grappling with this as well, with Marco's point of view appearing to win out at least in the immediate term with his attack on Earth at the end of the season. 

In Cibola Burn, Basia—Lucia's husband and fellow refugee from Ganymede—is a main point of view character. In the book, he instead of Lucia is the one who is part of the cell that blows up the landing pad that kills dozens from the UN-backed corporation. The show made Lucia the focus character on Ilus instead, in part because having Basia be the focus felt a little too similar to Prax's role in earlier seasons. 

There are other changes too of course, small things like not seeing more of the alien flora and fauna described in the book (I would have loved to see one of those "lizards" who throw up their entire stomach when eating something, but I understand that the CGI budget was better spent elsewhere). And if you've already read Nemesis Games, it's exciting to see where things are headed for Season 5. "Think about how much we get out of showing Marco and Naomi the way we do in episodes 4 and 5 of this season," Shankar teased. "That's a huge advantage of the material we created for Season 4 that isn't in the books; the material bridges Books 4 and 5." And while we'll likely have to wait another year to see how Season 5 plays out, fans of both the books and the show know what we get will be, to put it one way, Earth-shattering.