Avasarala died on Luna after a bout of illness. Duarte decrees that she will be interred in the mausoleum on Laconia, her funeral held in the State House. Holden--still being held prisoner by Duarte--meets Avasarala's granddaughter, Kajri. The High Consul asks to see her.
Duarte's edict that Laconia is the center of humanity was met with little resistance; everyone important has come to Laconia. Holden meets Drummer at the reception, who is still the figurehead of the Transport Union. She says the underground still has malcontents; he says he's waiting to strike.
On the Falcon, Elvi Okoye discovers a giant diamond larger than Jupiter in the Adro system. Duarte sent her to the dead systems to find out about the beings that killed the protomolecule creators, and why they left the "bullets" behind. Her husband Fayez thinks they compressed all the organic matter in the system into the giant green diamond.
Admiral Mehmet Sagale is the military commander of Elvi's mission. He keeps Elvi on schedule and says they need to use the catalyst--a criminal woman infected with protomolecule, kept in a Faraday cage to stop it from communicating. Elvi apologizes to her.
Naomi and Alex left the Roci in a cave on Freehold; Amos went silent after a mission into enemy territory; Bobbie is the captain of her own ship. Naomi is the secret general of the resistance, living in isolation in shipping containers aboard the Verity Close ice hauler. She meets Alex and Bobbie, who smuggled the Laconian Ship Gathering Storm into Sol. Bobbie's ship is crewed up with Belters, MCRN, and UNN vets. Saba, Drummer's partner and leader of the resistance, sent Amos to Laconia with a pocket nuke to save Holden. Naomi disagrees with Bobbie's direct military approach.
After a tear-ridden hug goodbye, Alex and Bobbie leave to oversee the transfer of the Storm onto the Pendulum's Arc. Bobbie's second in command is Jillian Houston, daughter of Freehold's mayor Payne Houston.
Teresa Angelica Maria Blanquita Li y Duarte, Consul Duarte's daughter, has lived in the state house all her life. Duarte tells her he's going to train her to be the next high consul in case anything happens to him.
The catalyst causes EM activity on the planet that mirrors the catalyst's fMRI readings, with spikes similar to the gates. Elvi theorizes the diamond-planet is actually the backup drive for the entire civilization. Sagale is mildly impressed, but still takes the Falcon to the next system on schedule.
The Storm strikes a Transport Union freighter escorted by 2 Laconian frigates. Alex and copilot Caspar Asoau attack the frigates while Bobbie and her marines breach the transport ship. The Storm takes some PDC damage that knocks out communication, and Bobbie's pod is damaged, leaving Alex no way to communicate with her. The politician they were there to capture is killed, but they find the mother lode of supplies.
Teresa learns that the boy she likes, Connor, kissed a girl named Muriel. Upset by the news, she takes a walk in the woods and runs into Holden. He stresses twice that she should keep an eye on him, before she's called away by Colonel Ilich, who says her that her father needs to see her about a security matter involving piracy.
Elvi has an adverse reaction to the meds needed for their hard burn to Tecoma, but ultimately seems OK. They find a giant neutron star on the verge of collapsing into a black hole, but absolutely nothing else. Sagale tells Elvi of their secret mission: they're going to push the gates to their threshold, then send in a bomb ship.
Bobbie feels that maybe Alex is right about the war being unwinnable, but finds that one of the looted crates is filled with antimatter spheres and she realizes how they can win.
Naomi gets a video update from Holden. At the end, Duarte asks her to come to Laconia to advocate for change in a non-violent way. He warns that there will be consequences if she continues down her current path. She gets an alert that the Tempest is coming to do a full inspection in 18 hours.
Teresa and her dog Muskrat sneak out to visit Timothy using a secret flood tunnel. Timothy lives in a cave filled with alien repair drones. She tells him about her father training her and mentions what Holden said; Timothy says she better listen to the captain. She says that her life is perfect, but has bitterness in her voice.
Later, she watches surveillance footage of Holden and sees him talking to a drunken Dr. Cortázar, who says Duarte has decided that Teresa will become immortal like himself.
Naomi has her face injected with something that makes it all puffy, and joins the heat sink crew so she can wear a mask. Laconian soldiers inspect the crew, but Naomi doesn't register on the scanner; the engineer says it's because she's an apprentice. Later, the engineer says it was his pleasure to help her, and gives her an access card for a private cabin.
Sagale sends the bomb ship through. It disappears and when the antimatter bombs go off, there is an increase in virtual particle activity in the system, but no one loses consciousness. They realize the particles will cause the neutron star to collapse and prepare to go on high-burn.
Bobbie tells Alex about the neutron bombs and says she wants to use then to blow up the Tempest. Alex says the plan is suicide.
The Laconian military issues a statement saying that travel through the gates has been suspended, and that everyone en route to one needs to move back to 0.8 AU.
Elvi's ship makes it through the gate and into the slow zone. Medina station is firing up to move out of the way of the gate, as the neutron star will send a gamma burst through the gate, which will also hit the alien station, causing all the gates to emit an even more massive burst of raditaion. Sagale makes for the Laconian gate, but the ship goes offline. The space around Medina glows white, then rainbow-colored. Segale orders all traffic through the gates to be suspended. All the gates have moved, and the Tecoma and Thanjavur gates are gone.
Duarte briefs Teresa about Tecoma and says that if they stop bombing the gates, it will show the "Goths" that humans are undisciplined--though he's not sure they can win. He says she'll understand once she's an immortal because he sees so much more now.
Duarte's official response is that any time a ship goes dutchman, they send another bomb ship through; making everyone unconscious may have killed the protomolecule designers, but has no affect on humans. Elvi thinks it was a trap. They notice radiation coming from in between the rings--then they all explode into atoms. Elvi sees tendrils of darkness moving; she screams and the tendrils drop away, and she returns to normal. Swaths of bulkheads, decks, and equipment are gone; erased. A loop of Segale's head is gone; Fayez's foot is gone; Elvi is missing a chunk of her thigh. The Falcon is in Laconian space.
Teresa visits Timothy and they experience atomic deconstruction like on the Falcon. She heads back, but is picked up by Ilich in a chopper, who tells her she has a locator chip implanted in her jaw. Her father is completely mindless--the alien attack may have affected him because of his protomolecule transformation.
Naomi, now on Auberon's lunar base, tries to contact Saba about the incident, but the repeaters, Medina, the Tempest, everything but the ring station is gone.
The news feeds report that Admiral Trejo is returning to Laconia, and Bobbie says now is their chance to strike. He asks her to run it by Naomi first, and that if she agrees, he's on board.
Teresa tells Holden that Elvi and her crew are there, but injured. He deduces that something must've happened with Duarte and is ready for the the next part of his plan.
With Saba's fate unknown, Naomi takes over running the underground.
On Laconia, Trejo tasks Elvi with fixing Duarte. The Voice of the Whirlwind will guard Laconia, the Tempest will remain in Sol, and 280 destroyers will police the gates. Trejo says he will continue to attack the aliens. Fayez talks with Holden; he relays that Holden thinks Cortazar is plotting a murder.
Teresa tells Timothy everything that's happened. Ilich and 3 guards track her down, and a firefight breaks out when they see Timothy. Ilich and some of the guards are wounded, and Timothy is shot in the leg and the head. Trejo tells her Timothy was a terrorist named Amos Burton and demands to know everything she told him.
Naomi gets Bobbie's message and tells her to go forward with the attack.
Elvi tries to track down Holden, but he's thrown in custody after Amos is found with a pocket nuke. She is taken to the Pen and Cortazar shows her 2 Laconian children who died 20 years ago, but were "fixed" by repair drones. They have black eyes, gray skin, and they haven't aged at all. Cortazar says the repair drones in the cave got to Amos, and his body was not recovered.
Bobbie tells her crew that the Tempest has a blind spot and that she's going to leave a shuttle full of antimatter bombs in its path, using the Storm as bait. She'll pilot the shuttle.
Teresa visits a badly beaten Holden in his cell, who says he knows nothing about Amos. Trejo no longer trusts Ilich. Cortazar takes Teresa out of class for a "routine medical checkup"; Elvi is waiting for them in the medical bay, says if something's wrong with Teresa, Cortazar should tell Trejo. He lets her go back to class.
Bobbie shuttle is hit by Tempest's PDC rounds and the antimatter torpedo is damaged. She launches herself and the torpedo out of the shuttle using her power armor, putting the bomb on a ballistic path toward the Tempest. She goes out guns blazing, but is hit by a PDC round. The torpedo hits, vaporizing the Tempest.
The Storm was too close to the blast and everyone onboard gets cancer--even the ship itself seems sick. Julian takes permanent command and asks Alex to be her XO, but he declines, saying he has his own ship. They head back to Freehold.
Elvi tells Trejo that she thinks Cortazar is trying to kill Teresa; he says Cortazar is indispensable, and that anything to restore Duarte is on the table, even killing his daughter.
Naomi gets a message from Alex about Bobbie and says he's going back to the Roci. She decides to head to Freehold too.
Teresa hasn't been eating and passes out in class. Elvi tells her she thinks Cortazar is trying to kill her to test bringing her back with repair bots.
Alex finds the desert cave on Freehold where they left the Roci, and she's still in good shape. A few days later, Naomi shows up. They get the Roci back into space; they lose time again--20 minutes.
Cara and Alexander tell Elvi that when they were repaired, they were given vast knowledge that they refer to as the "library", which Duarte didn't seem to have access to. She meets with Trejo, et. al. about the most recent blackout, which appears to have affected all the systems, and ships in the ring space disappeared again. Elvi thinks the the aliens are trying different attacks; humans are more resilient than the protomolecule creators, since they were just a mass consciousness. She thinks going through the gates, using their weapons, etc., is hurting the "dark gods." She tells Trejo that she doesn't think they can fix Duarte, and the realization finally hits home. Elvi wants to tells everyone the truth, and thinks Laconia should surrender so humanity can form a united front.
Teresa tells Duarte that Cortazar is going to kill her, and he seems to react for a second. Ilich shows her Amos's notes, which include different points of attack, but she remembers how he protected her during the gun fight, and how Holden told her that if Amos called her a friend, he meant it. Ilich forces her to eat and tells her not to miss class tomorrow. She decides this is no longer her home.
Naomi has over 400 ships at her disposal. They all line up in the slow zone around Draper Station and wait to proceed into the Laconian gate. Naomi tells everyone that the plan is to destroy the Laconian construction platforms so they can't make more warships or antimatter. They storm the Laconian gate. The Storm seems to be the Laconian defense's first target.
Cara tells Elvi that the giant green diamond is a record of everything all at once. Trejo warns of the impending invasion and tasks Elvi with scanning Duarte to put out a fake statement. While prepping the scan, Duarte notices Cortazar, walks towards him, makes a gesture, and Cortazar's chest explodes. Trejo grants Elvi access to Cortazar's files; she finds over 100 files he kept hidden from her.
Naomi's fleet fares well against the Laconians; her ships are restocked from all the other systems, but the Laconians have no backup. Her ships bombard the planet with rocks and nukes; whenever Laconian ships chase them, they retreat. She fakes a ship malfunction and lures the Whirlwind away from Laconia; the other ships make for the construction platforms and launch their attack. The Roci gets an evac request from Amos.
Cortazar's notes show he intended to kill Teresa and feed her to the repair drones--an idea suggested by Holden. At Teresa's 15th birthday party, she asks Elvi about escaping on the Falcon, but Elvi and Fazyez tell her it's in pieces; Teresa says they should expedite the repairs then.
Teresa shocks a guard with a cattle prod, and breaks Holden out. He dresses in a guard's uniform, and Teresa takes him to Timothy's belongings, where she activates his evac transponder.
Elvi and Fayez go to Teresa's room and find only Muskrat, who leads them to the mountain where Holden and Teresa are. She tells Holden not to hurt Teresa; he says he wasn't actually planning on it, that he was trying to replace Cortazar with Elvi by telling Duarte about Cortazar's plans. Elvi says if she leaves that she'll lose all her research, and tells them to go without her.
The Roci takes out the Laconian platforms, but spins out of control when they hit the last platform; the Laconians were making antimatter and the explosion was enormous. Naomi tells the remaining ships to head back while they attempt to land and make the rescue.
Teresa and Holden are intercepted by Ilich and some guards; Ilich tells her to get in the cart or he'll shoot her dog. Amos, with black eyes and gray skin, attacks the security guards and shoots Ilich, taking a bullet in the process, though this doesn't seem to affect him. The Roci lands and they all board to a round of cheers. As they're leaving, they are target-locked by the Whirlwind.
Naomi gets a tightbeam from the Whirlwind; Teresa tells Admiral Gujarat to stand down--she's on a secret mission working with the underground at her father's behest. The admiral won't let the Roci go, so Teresa tells Gujarat to "shoot her the fuck down then" and drops the connection. Alex takes the Roci out.
Naomi asks Amos why he never set off the nuke; he says it didn't feel right killing the kid. They hold a ceremony for Bobbie and cast an empty coffin into space. From the start of the campaign, they'd lost 32 ships, just shy of 200 people, but now the Whirlwind was stuck protecting Laconia. Naomi tries to connect with Teresa, but she's miserable and says she can't stay. Holden says they should try to find some of her relatives that didn't defect with her dad.
Elvi tells Trejo that she is going to check out the giant green diamond next, and that he needs to surrender to the underground instead of trying to prolong the war, because they have much bigger fish to fry. She tells him to arrest her for insubordination, or get the Falcon repaired for her. She goes to the Pen and tells Dr. Ochida to shut the Pen down; they don't need more protomolecule samples anymore and they don't need to inject it into prisoners. She frees Cara and Xan and asks if they can help her.
Naomi remains the admiral of the resistance fleet, but Holden is back as captain of the Roci. He has a talk with Amos and asks him if he's still Amos; Amos assures him he is, he just knows things he didn't used to, like that the aliens Duarte pissed off are going to kill everybody. Holden says he knows that too.