Leviathan Falls is the ninth novel in The Expanse series and marks the end of the book series and was released on November 30, 2021. It was originally projected to be released on November 16, 2021, but production delays with the publisher postponed the release to November 30, 2021. 
Its title and cover were revealed by publisher, Orbit Books, on September 16, 2020.
The Laconian Empire has fallen, setting the thirteen hundred solar systems free from the rule of Winston Duarte. But the ancient enemy that killed the gate builders is awake, and the war against our universe has begun again.
In the dead system of Adro, Elvi Okoye leads a desperate scientific mission to understand what the gate builders were and what destroyed them, even if it means compromising herself and the half-alien children who bear the weight of her investigation. Through the wide-flung systems of humanity, Colonel Aliana Tanaka hunts for Duarte’s missing daughter. . . and the shattered emperor himself. And on the Rocinante, James Holden and his crew struggle to build a future for humanity out of the shards and ruins of all that has come before.
As nearly unimaginable forces prepare to annihilate all human life, Holden and a group of unlikely allies discover a last, desperate chance to unite all of humanity, with the promise of a vast galactic civilization free from wars, factions, lies, and secrets if they win.
But the price of victory may be worse than the cost of defeat.
On Laconia, Winston Duarte is slowly recovering from his conscious mind being turned off from a time skip event. He overcomes the effects through his sheer will to protect his daughter Teresa Duarte. After his recovery, he projects himself into Trejo's mind, who is in the Sol system reconquering it for the Laconian Empire. Duarte thanks Trejo for holding the Empire together but tells him they were thinking too small with their attentions. Duarte then vanishes from Trejo perspective and orders his ship to do a hard burn back to the Laconia system.
By the time Trejo returns, Duarte had already then left the state building on Laconia. Trejo dispatches Colonel Aliana Tanaka to find him, giving her the highest level of clearance, second only to his own. She investigates the area on Laconia where Teresa took her walks, and tracks Duarte to the cave Amos Burton lived in. She goes further into the cave network and discovers a place where the repair drones bring things to pools of some sort where they are repaired. Tanaka determines that Duarte left in some sort of small ship; he could be anywhere in any of the systems in the Ring network. She decides the best way to find him is to use Teresa as a lure, so she sets out to find her. Her investigation turns up a relative of Duarte who runs a girls' boarding school on one of the colony worlds, and decides to investigate it as a likely location for Teresa to be sent.
Elvi is investigating the Adro Diamond aboard the Falcon with a full science team, Xan, and Cara. They use The Catalyst to trigger interactions between Cara and the Jupiter-sized diamond to dive into The Library, putting Xan in the Catalyst containment chamber during the 'dives' to isolate him so he and Cara don't have any interactions and also so he can act as a control subject. Some of Cara's experiences during the dives bleed over into Amos, on the Roci.
The Rocinante and its crew (Jim, Naomi, Alex, Amos and Teresa, who has become a sort of apprentice to Amos) are just trying to avoid Laconian ships as Naomi continues to run the underground with her bottles. Alex receives a message from his son, Kit, who is now married, has a son, and will shortly be moving to the Nieuwestad system and its colony world. As they are exiting the Sol gate to send a message from Alex to Kit, they see a small ship enter the ring space at high speed from Laconia. After sending their message, they transit the ring space to New Egypt to take Teresa to the boarding school, something she reluctantly agrees to. On their way down the well, they see a Laconian ship a little way behind them, and decide to land on New Egypt when it's on the other side of the planet just to be safe.
Jim and Amos accompany Teresa on the walk from the Roci landing site to the school. They've arrived a few weeks before term so other students haven't arrived yet. Approaching the school, they are met by Tanaka, who says she just wants the girl and the others can leave. Amos spots a Marine fire team hiding on the roof of the building and covertly opens a comm link to Alex who recognises the trouble and gets the Roci ready to assist. After some back and forth, the Roci can be heard approaching and Tanaka tells the ship hiding on the other side of the planet that the Roci is not to be allowed to leave the system with Teresa, gets tired of talking and tells the Marines to bring her the girl. This does not go well for them.
As they approach the trio, the Roci is able to kill them all with PDC fire, an extremely reckless move that shocks Tanaka. Tanaka hides in the building as Jim, Amos and Teresa run to the Roci. Tanaka runs around them, hiding in the tall grass, and arrives in front of Jim and Teresa. Just as she is about to kill Jim, Amos reveals that he is behind her, and attacks. Combat ensues. Jim shoots Tanaka in the chest, and she goes down. The trio make their way to the Roci. Tanaka had armour under he clothes and is mostly ok; she shoots Amos in the back and his chest explodes. Jim manages to shoot her in the face (she survives); he and Teresa get what's left of Amos into the Roci and they take off.
In orbit, the Roci is at a standoff with a Laconian frigate, the Sparrowhawk. The frigate stalls, then fires torpedoes to take out the Roci's drive cone, and the Roci returns fire with their railgun and are able to damage the enemy ship enough to escape, after shooting down the torpedoes. After the engagement, Amos walks onto the command deck, having healed from his seemingly fatal injuries. They decide to go to Freehold and Draper Station, for resupply. Unfortunately, a Pulsar-class destroyer, the Rising Derecho, is in the system, orbiting the main planet, trying to coax the underground to surrender the Gathering Storm by means of threats to the Freehold populace. Tanaka has sent word to all Laconian ships to report sightings of the Roci, and the Derecho is able to identify the Roci's silhouette and drive signature, so she will be on her way soon, having had her face somewhat repaired by the medic at the school.
The Roci covertly makes its way to Draper station when it is hidden from the Derecho's view by a planet, and gets resupplied. The Sparrowhawk arrives in the system and transmits a message from Trejo to Naomi: it is an offer of alliance between the Laconian Empire and the underground, whereby Naomi's protocols for gate travel would be used to ensure no Dutchmans would be caused by the Laconian Imperial Navy with her oversight. He also requires that Teresa be returned to them but says the agreement would allow him to pull back his ship and threats from Freehold.
The crew agree that Trejo's requests are unreasonable. Unfortunately, Jillian Houston has taken things into her own hands, locking the Roci crew into their quarters and evacuating the atmosphere from the surrounding rooms. She invites an envoy from the Sparrowhawk to come collect the girl. Tanaka comes, in some very fancy armor, with no real intention to honor Trejo's deal. She meets Jillian and four guards. Jillian realises that she screwed up. After some conversing, Tanaka has her suit kill the four guards. Jillian runs, and Tanaka begins her rampage through the station.
Jillian releases the Roci crew and tells them to get out, and also instructs the crew on the Storm to prepare for departure. The forces on the station are able to slow Tanaka's advance slightly with an improvised missile (a heavy canister propelled with compressed gas). This leads her to declare to everyone in the area that whoever brings her the girl will be the one person she allows to leave the station alive. She finds Jillian and chases her, sort of playing with her by not killing her even though she almost certainly could. Jillian makes it inside the Storm and closes the airlock door just in time, as a grenade from Tanaka explodes against the outer door. She has the ship take off immediately. The Roci follows shortly. The Sparrowhawk is close and the Derecho is on the way. She decides that there's only one thing left to do.
Captain Noel Mugabo of the Sparrowhawk offers Jillian the opportunity to surrender, telling her that even if she destroys his ship, the Derecho will destroy hers. She declines, telling him: "We have a few minutes still, you can send a message, I would let your superiors know that when Colonel Tanaka opened fire without provocation on Draper Station, she didn't just kill us, she killed you, too. I hope it was worth it." The Storm destroys the Sparrowhawk before engaging, and being destroyed by the Derecho.
The Roci is running for the gate, with the Derecho in pursuit, quite far behind having had to pick up Tanaka and possibly being limited in speed due to damage sustained against the Storm. Amos says they need to see Elvi, so the crew decide to go to her in the Adro system. Tanaka has the Derecho hold back on its burn towards the gate, hoping to make the Roci crew relax, planning to push the ship to the point of killing some of its crew after the Roci passes into the ring space with the aim of arriving in time to see the remnants of the drive plume pointing to where the Roci went.
The Derecho arrives in the ring space and begins scouring the area for remnants of a drive plume. A large ship recentlly transited to the Bara Gaon system and the Derecho crew/computer identify the remnants of this plume as that of the Roci plume. At the same time, a large ship is transiting into the ring space from the Sol system. It's the colony ship that Kit and his family are aboard and it begins to go Dutchman. However, partway through the process, it goes back to normal, somehow surviving. Those inside the ring space and aboard that ship at the time also go through something strange. They experience things from others' memories for a short time. This is deeply distressing for Tanaka as her secrets are important to her. As this happens, the rings begin glowing, inside and out. The Roci crew see this as they make their way from the gate to where the Falcon is stationed.
The Ring Entities have been attempting to kill humans by various means. Some of these manifest as the cognitive events people have been experiencing, but Laconian science teams are also able to identify that some of these events resulted in the speed of light —the speed of causality— changing for a short period of time within some systems. Most of these don't have too much effect on humans, other than causing unconsciousness for a few minutes sometimes. However, one event in the San Esteban system did have a drastically more significant effect: all but the most basic life in the system was wiped out. The change made resulted in ionic bonds to change for a very, very short time, but enough to prevent most affected life from functioning properly by shutting down neurons, and killing every person and complex life. Elvi surmises that the reason the Ring Entities haven't realized that they have the solution to their problem is that they can't observe our universe any more than humans can the Ring Entities', and so the entities are relying on traffic through the gates to indicate success. Even after all the life in the system was wiped out, humans continued using the gate to the system, so the Ring Entities do not know that their tactics have worked.
The Roci reaches the Falcon and the two ships dock. Elvi and Fayes hope no one aboard kills them for treason. After some discussion, they decide to do a dual dive involving both Cara and Amos. Through this, those in the room with the divers (or "Dreamers") are able to see Winston Duarte. He tells them that humanity must become more like the him. He wants to create a hive mind encompassing all humanity. He's already taken the first steps and is now able to prevent the Ring Entities from attacking this universe or making ships go . The entities' attacks have also stopped.
On Bara Gaon 5, Tanaka realizes she's followed the wrong ship. The Derecho docks at a station to resupply and repair and Tanaka begins having more of other peoples' experiences. She decides to go see a doctor about it, but, at the last moment, says it's about her face. She gets a more complete repair done on her face and, after waking up, overreacts and attacks the doctor over something small. She decides she's needs psychological help and goes to the receptionist to arrange a psychological evaluation.
Following multiple dives by Cara into the Library in Adro Diamond, Cara sees the origins of the Ring builders. She with the help of Elvi, learns that they originated and evolved as a very alien, aquatic, parasitic hive-mind species on the oceans an ice moon of a gas giant. However after the duel dive test Amos and Cara did, Amos goes to Elvi and tells her the dives with Cara need to stop. After some back and forth, she agrees. Cara later finds out about this and is not happy. She's been developing a sort of dependence on the dives as they've become additive, and Elvi has seen this in her neural activity.
The psychiatrist/psychologist provides Tanaka with some medication that might help to block the spontaneous neural activity involved in the experiences she's been having, along with many others who were in the ring space when the ship didn't go Dutchman. The medication helps, but the problem is spreading to those who weren't in the ring space at the time as well. She receives word that Laconian scientists think they've found the egg ship Duarte took: it's on the Ring Station.
Elvi and the Roci crew also learn that Duarte is most likely on the Ring Station, and make preparations to go there. Naomi also sends Trejo a message, accepting his previous offer and providing the data relating to the dual dive experiment, as well as transmitting all the data in Trejo's original message to everyone else in the underground, and she has the underground send as many ships as possible to the Ring Space.
Trejo orders Tanaka to figure out what Duarte is doing, and either get him back or take control. Tanaka has the Derecho prepare to leave as soon as possible, and does some shopping: she collects all the medications she was prescribed as well as any others that could have similar effects available on the station, as well as the materials to make more on the ship after they've left, and the ship proceeds to the Ring Space.
The Roci and Falcon arrive and begin conducting scans of the station, as more ships, Laconian and underground, arrive, using Naomi's transit protocols which are working well. Afterwards, Tanaka and the Derecho arrive. Tanaka provides the medication she's brought, and tells them they'll need it if they want to stay themselves. They all discuss their next steps: they decide that Tanaka will go in with Teresa to try to get Duarte to stop what he's doing; they just need to figure out how to get inside. They try a dive, with Amos, against Cara's protestations. Cara and Xan are in the Catalyst containment chamber to keep them isolated. The dive does not go well, and the science team are unable to bring Amos out of it. Elvi runs to the Catalyst room and brings Cara out, asking her to help him. She does, and Amos returns. He says Duarte is pissed with them.
Jim realises that there's only one thing to do. He has an emotional scene with Naomi where she tells him to wait until she's asleep before he does whatever he's going to do. He does. After she's asleep, he goes to the Falcon, to the Catalyst room, where he opens the Catalyst chamber and extracts some protomolecule from her/it, which he then injects into himself, allowing him to see and speak to Miller again.
After some discussion, it is decided that Jim, Tanaka and Teresa will go into the ring station, with Jim using the newly reactivated Miller inside him to gain access. This new Miller has some upgrades: because Jim now has actual protomolecule inside him, Miller no longer disappears whenever someone is around; Jim gets to see and hear him at all times. However, because he is only in Jim's head, he doesn't have quite as much access to information as the original proto-Miller did.
Miller is able to open the Ring Station for Jim, Tanaka and Teresa, and they head inside. As they go deeper, they find the station has a breathable atmosphere, and surmise that Duarte must have had it created since he didn't bring a vacuum suit with him. Tanaka attempts to use the sensors of her suit to track Duarte's scent, based on readings she took of his clothes before she first left for the cave. Unfortunately, it proves less than effective. Jim begins deteriorating, appearing distant at times, and Tanaka tells Teresa that she needs to be prepared for her to *handle* him. Jim suggests that Tanaka look for a heat source, as that's how the original Miller was able to find Julie Mao on Eros all those years ago. This proves more useful.
Meanwhile, in the Ring Space, more ships continue to arrive. However, some of the incoming ships break contact; it seems Duarte has gained control over their crews, and is now bringing them to the Ring Space to stop those who would oppose him. Distressingly, the Voice Of the Whirlwind, the last of the Laconian Magnetar-class battleships, is among those silent ships on their way. Naomi begins preparations to coordinate her fleet against the incoming onslaught, at least until the Whirlwind arrives.
The team inside the station come across some sentries which, while not immediately attacking them, seem unwilling to allow them to pass. Tanaka's first tactic is to shoot them, but Jim stops her from trying this. Miller is able to interface with the sentries and they allow the trio to pass. Eventually, they find Duarte, who is in some sort of web, connecting himself to the Ring Station. Teresa tries talking to him, but he seems uninterested in turning away from his plans to become the God-Emperor of a human hive mind. As the first enemy ships begin arriving in the Ring Space, Naomi does her best to coordinate her forces against them, and has some success. Unfortunately, some within her group act independently and get themselves separated from the rest of the formation, making themselves easy pickings for the attackers.
Teresa lashes out at the web, doing some damage to it, to which Duarte reacts with extreme pain. Unfortunately, the sentries also react, a lot of them. Jim gets Teresa away from Duarte, and Miller is able to provide some aid by turning the sentries off, but Duarte keeps turning them back on. They are all over Tanaka, but she triggers the emergency release on her suit, blowing it apart and allowing her some freedom from the sentries, at least until they catch her. She runs for Duarte and breaks his neck. Naomi's forces continue to be whittled down slowly but surely. And then, the Whirlwind arrives and begins making its way towards the Ring Station.
Jim tells Tanaka that Duarte isn't dead, and indeed he isn't. She starts ripping him apart with her bare hands, breaking into him and trying to destroy whatever is left inside. At the same time, the sentries are trying to stop her, mortally wounding her, but she is able to do enough to what used to be Duarte that he doesn't survive either. Tanaka dies knowing Jim is still alive, something that she does not enjoy after he shot her in the face. Teresa is distraught and Jim does his best to comfort her.
In the Ring Space, the attacking ships stop their march, and the commander of the Whirlwind sends a message asking what the is going on. Elvi responds and then things begin to worsen again. With Duarte gone, there's nothing holding the Ring Entities at bay, and they begin pulling ships inside the Ring Space apart again.
Inside the station, Miller informs Jim that, without Duarte, everyone outside the Ring Station is back in danger. Jim puts the pieces together and takes Duarte's place connected to the station. He is able to halt the attacks with a little guidance from Miller. However, he doesn't want to be a God-Emperor like Duarte; he didn't come here to stop Duarte from creating a hive mind of all humanity with him at the center, just to become the center himself. He decides the Ring Builders did it wrong: they only turned off the ring gates, but they kept the ring station, using a bandage without removing the splinter first. He reaches out to Amos and tells him to tell Naomi to evacuate the ring space: "Get everybody out, and wherever you go, be ready to stay there." He adds that Amos should wait for Teresa. He modifies the Ring Station to make a path for Teresa to get out, and tells her to run.
Naomi sends the message that everyone must leave and be ready to stay in the system they go to. Elvi decides the Falcon will go to Sol, as she probably wouldn't be welcomed on Laconia given her treason, and Naomi says they're going there, as well. Alex mentions that his son is in a different system and that he'd like to go there. Naomi decides that Alex should take the Roci and she, Amos, Muskrat and Teresa (when she arrives) will go on the Falcon. They say goodbye and Alex makes way for the ring to the system his son went to. Once Teresa arrives, the Falcon makes way for the Sol gate.
As the ships leave the Ring Space Holden's ability to hold off the Ring entities gradually weakens as he feels them still pushing into the Ring space. However after the last ship leaves and the Ring Space is left completely empty, Holden converses with Miller over the decision he is about to make. Miller tells him he would be consigning millions of people to a slow death on all those hundreds of worlds that are not self sufficient and asks if he is making the right choice. Holden response with him telling Miller he has no clue and then destroys the Ring Station with an explosion only second to that of the big bang. With the Ring space destroyed, the Ring Entities loose their ability to interact with the human universe. The Ring gates then all shut off, collapse, and begin falling towards their local stars, no longer able to hold themselves in place without the energy supplied from the Ring Space and Station. The 1,300 colony systems are now on their own and will have to find their own way to the stars.
A thousand years later, a linguist named Marrel Imvic is onboard the Musafir in Dobridomov system, which is a member of the Thirty Worlds. Marrel and his team travel from Dobridomov to the Sol system, 3,800 light years away, in just 31 days. This is possible with Musafir's superluminal propulsion, which is capable of entering the space in-between our universe and that of the Ring entities. When they emerge from this subspace and arrive, Marrel notices how the space around Earth is empty. There are still structures in the system, including some disguised weapon emplacements and hidden ships, but fewer than there had been in other contacted worlds. They then land on Earth, near an ancient city. He is met by a man who turns out to be Amos. Marrel introduces himself in ancient Chinese. Amos asks if he speaks English, Marrel says he does. Amos explains how it's been a rough millennium on Earth and with only recently getting things back together with his help. After Marrel eases Amos that he and his party of diplomats are not here to cause trouble, Amos tells them to follow him to "grab a few beers and get reacquainted."
- Duarte (prologue)
- Trejo (prologue)
- Jim (12⅚ chapters)
- Tanaka (11¼ chapters)
- Naomi (7½ chapters)
- Elvi (7 chapters)
- The Dreamer(s) (5 interludes)
- Kit (2¼ chapters)
- Fayez (1 chapter)
- Teresa (3 chapters)
- Jillian (1 chapter)
- Ekko (⅙ chapter)
- Alex (3 chapters)
- The Linguist (epilogue)
The book was first released as a hardcover by orbit on Novemeber 30, 2021,
The book was released as a trade paperback in the U.K. on December 2, 2021.
- Polish: Upadek Lewiatana (2022)
- German: Leviathan fällt (2022)
- French: La Chute du Léviathan (2022)
- In an interview with Polygon, Daniel Abraham and Ty Franck mentioned that they knew Leviathan Falls’ last line — Naomi Nagata musing, “The stars are still there. We’ll find our own way back to them” — since they were writing the second book, Caliban's War.
- The title refers to the fall of the Protomolecule which contrasts with the title of the first book, Leviathan Wakes.
- Leviathan is a Biblical allusion to the Leviathan, a large sea monster referenced in the Tanakh, or the Old Testament and is also a reference to the book Leviathan by the English philosopher Thomas Hobbes.
- Leviathan Wakes - novel
- Caliban's War - novel
- Abaddon's Gate - novel
- Cibola Burn - novel
- Nemesis Games - novel
- Babylon's Ashes - novel
- Persepolis Rising - novel
- Tiamat's Wrath - novel
- The Churn - novella
- The Vital Abyss - novella
- "The Butcher of Anderson Station" - short story
- Gods of Risk - novella
- "Drive" - online short story
- Strange Dogs - novella
- "The Last Flight of the Cassandra" - short story
- Auberon - novella
- Memory's Legion - compendium
- The Sins of Our Fathers - novella
- Tweet from James S.A. Corey (May, 11 2018): Book nine is the last book of #TheExpanse, and book eight comes out this year, so the end is in sight.
- Hachette Book Group - Leviathan Falls
- Tweet from Orbit Books (October 6, 2021): Announcement of book 9's delay.
- Amazon - Leviathan Falls
- The final book in #TheExpanse series by @JamesSACorey is LEVIATHAN FALLS! Coming 2021.
Watch the authors answer questions from the audience during the live reveal: <URL not allowed>
Art by Daniel Dociu; design by @Planetpinto
- The Expanse authors were always building toward Leviathan Falls’ world-altering ending
- Daniel Abraham on Reddit Daniel Abraham confirms Leviathan reference January 26 2022
- James S. A. Corey - Leviathan Falls
- Tor.com - Leviathan Falls Will Be The Final Installment of The Expanse by Andrew Liptak Wed Sep 16, 2020 2:27pm
- io9 - The Expanse's 9th and Final Book Is Titled Leviathan Falls by Cheryl Eddy Sep 16, 2020 2:22PM