Babylon's Ashes recap

In the aftermath of the Free Navy's asteroid attacks, Marco Inaros holds Ceres, Medina Station and the ring space while Earth starves and the inner planets rebuild a fleet. His movement decays from within: his squadron commander Michio Pa defects and turns pirate, seizing Free Navy cargo and giving it away to Belt stations; Ceres is stripped and abandoned, handing the alliance a station full of starving people and handing the Belt a lesson about who Marco actually serves; Medina's own work crews turn against the occupation; and his son Filip, raised as the movement's heir, finally sees his father clearly. Fred Johnson dies and leaves his authority to Holden. Earth, Mars, Pa's ships and the Outer Planets Alliance combine, and Naomi works out how to use the ring gates themselves as a weapon. Baited into a mass transit of the ring, most of the Free Navy is destroyed and Marco with it. Filip, who left before the battle, survives anonymously. The powers that remain create a Transport Union to govern the gates and give the Belt a permanent place in the settlement of the new worlds.

Previously: the crew of the Rocinante, captain James Holden, engineer Naomi Nagata, pilot Alex Kamal and mechanic Amos Burton, were thrown together during a war between Earth, Mars and the Belt that had been engineered to cover a secret experiment with an alien organism, the protomolecule. The organism consumed the asteroid station Eros and then built a ring gate beyond the orbit of Uranus, opening onto a hub connected to more than a thousand gates and the habitable worlds behind them. Human settlement of those worlds began, and the Belt saw its future disappearing: its economy depended on being the crossroads of the solar system, and cheap new worlds threatened to make it irrelevant. Naomi's estranged former partner, the Belter revolutionary Marco Inaros, gathered the angriest factions into the Free Navy, obtained warships through a covert deal with a rogue Martian admiral, and threw stealth-coated asteroids at Earth, killing billions and wrecking the planet's climate. Their son Filip, raised by Marco, took part. The Free Navy seized Medina Station in the ring space and choked off traffic to the colonies. Earth's fleet was gutted, Mars was hollowed out by emigration, and the Belt split between those who cheered Marco and those who feared him. The Rocinante's crew, scattered during the attacks, reunited and made common cause with Fred Johnson's Outer Planets Alliance at Tycho Station, along with Clarissa Mao, a former enemy released into Amos's custody.

The Free Navy is at its height. Marco Inaros holds Ceres Station, Medina Station and the ring space, and his squadrons take shipping across the system at will. Michio Pa, commanding one of those squadrons from the Connaught, carries out his orders and keeps a careful private tally of what is seized and where it ends up; the answer is increasingly that it goes to Marco's friends rather than to the Belt. Aboard the Pella, Filip Inaros is treated as the heir to a revolution, celebrated for his part in the attack on Earth and given very little to do. At Tycho Station, Holden works with Fred Johnson to keep the surviving Outer Planets Alliance aligned with Earth and Mars, with Naomi and Amos aboard the Rocinante and Clarissa Mao working her way into the crew. Earth is dying by degrees under a wrecked sky. On Medina, welders including Salis are installing the heavy weapon emplacements that will make the ring space impossible to attack, and discovering that the new order polices its own people as hard as the old one did.

Michio Pa breaks with Marco. Rather than delivering seized cargo where the Free Navy directs, she begins distributing it to Belt stations that the movement has left to starve, and takes her squadron and her family crew out on their own. Marco treats the defection as a personal insult and diverts effort to punishing her. The alliance between Earth, Mars and Fred Johnson's faction slowly becomes real: Chrisjen Avasarala works to keep the inner planets committed to feeding the Belt rather than simply bombarding it, Alex Kamal and Bobbie Draper run the Razorback on errands that trace the black-market pipeline that armed the Free Navy back into the rot inside the Martian military, and on Ganymede the botanist Prax Meng's engineered yeast becomes the most strategically important research in the system, because Earth cannot grow food. Naomi begins broadcasting to Filip, openly and repeatedly, an invitation he cannot acknowledge without treason.

Marco abandons Ceres. The Free Navy strips the station of everything portable, wrecks what it cannot take, and withdraws, leaving the allied fleet a choice between occupying a station with more than a million starving people and letting them die on camera. Anderson Dawes, who had thrown in with the movement, is left with the consequences. The alliance takes the station and the burden with it, and the political cost to Marco across the Belt is severe. At Tycho, Fred Johnson dies suddenly, and the authority and the holdings he had built pass to Holden by arrangement, making the Rocinante's captain a power broker he never wanted to be. On Medina Station, resentment among the work crews hardens into sabotage aimed at the ring space defenses, and the Free Navy's response falls hardest on Belters who had nothing to do with it.

The alliance consolidates. Earth, Mars, the Outer Planets Alliance and Michio Pa's independent faction negotiate their way into a single command with a shared objective, and Pa extracts terms for the Belt as the price of her ships. Marco's coalition moves the other way: stations withdraw support, captains hedge, and his response to every setback is a search for traitors rather than a change of plan. Filip, who has watched his father lie about the Belt's dead, dismiss real losses, and stage victories for an audience, can no longer make the story he was raised on fit what he sees. The Free Navy pulls back toward the ring space, where its heavy emplacements make it effectively untouchable, and the allied fleet begins moving in the same direction.

Filip breaks with his father and walks away from the Free Navy, giving up the only identity he has ever had. Marco, unable to admit that the Belt is abandoning him, stakes everything on a decisive fleet action at the ring gate, where his rail guns and his numbers should be unbeatable. On the allied side Naomi works out that the gate itself is the weapon: the ring destroys anything that crosses it carrying too much mass and energy in too short a span, a limit measured in ships that have already vanished. The allied fleet is positioned to bait Marco into exactly the crossing that will trigger it, and the last preparations are made on both sides.

The trap closes. Marco drives the Free Navy through the ring gate en masse and at speed, and the gate consumes most of the fleet, the Pella and Marco Inaros with it. The war ends within hours. What follows is the settlement: the surviving powers create a Transport Union to govern all traffic through the ring gates, seated at Medina Station and led by Belters, guaranteeing the Belt a permanent share of the new worlds rather than obsolescence. Fred Johnson's holdings, inherited by Holden, are turned over to it. Ceres survives as a ward of the alliance, Earth begins the decades-long work of feeding itself with Prax's engineered strains, and Michio Pa's faction is folded into the new order. Filip, who left before the battle, is alive and anonymous, working an ordinary berth under another name. Bobbie Draper joins the Rocinante's crew, and the ship takes union contract work: for the first time in a decade, Holden and Naomi have nothing catastrophic to do.

Marco commits the Free Navy to a decisive battle at the ring gate rather than accept that his authority is evaporating. The allied fleet gives him the fight he wants on terms Naomi has calculated: the gates destroy anything that passes through them carrying too much mass and energy at once, and the Free Navy's ships transit together at speed. Most of the fleet, the Pella and Marco Inaros with it, is annihilated in the crossing. Filip is not aboard; he had already broken with his father and walked away, and he ends the book working an ordinary berth under a name that is not Inaros. With the Free Navy gone, the surviving powers build a Transport Union to govern traffic through the ring gates and to give the Belt permanent standing in the settlement of the new worlds, with Belter leadership at its head and Medina Station as its seat. Fred Johnson's holdings, willed to Holden, are folded into it. Earth begins the long work of feeding itself again with Prax's engineered strains; Michio Pa's faction is absorbed into the new order; Ceres survives as a ward of the alliance. The Rocinante takes contract work for the union with Bobbie Draper added to the crew, and Holden and Naomi, having spent a decade at the center of every catastrophe, are left with the unfamiliar prospect of ordinary work.