Death's End

Of the many Wallfacer plans, only Luo Ji’s is a success. At first, what he does is mystifying: He broadcasts the location of Star 187J3X1—a star unconnected to Earth or Trisolaris—to the universe. However, soon, that star’s system is destroyed when an object is launched into its sun at near light-speed.

Luo Ji has realized that the universe is like a dark forest, in which civilizations seek to destroy any others they discover to protect themselves and gain access to finite resources. The destroyed star is an example of a dark forest strike. After the Doomsday Battle, Luo Ji threatens to reveal the location of Trisolaris by broadcasting a similar message to the universe containing Trisolaris’s location. However, analysis of this message will also reveal Earth’s location, locking the two civilizations in stalemate of mutually assured destruction. The threat works; the Trisolaran Fleet changes course away from Earth.

All technological communication ceases for a short time until humanity is confident no one in the universe can hear them.

The crew of Bronze Age believes this silence is the result of the Trisolarans conquering Earth, until a message arrives explaining the new Dark Forest Deterrence. The command of the Bronze Age decides that as survivors, they are heroes and should return. When they get back to the Solar System, they are escorted by Gravity, a new ship with the capability of broadcasting Trisolaris’s location to the universe. However, when the ships dock, the crew of the Bronze Age is accused of crimes against humanity and arrested.

The Bronze Age trial reveals that the crew descended into totalitarianism in only five minutes. According to crewmembers, the conditions of space and the belief that they would never return home influenced them to attack the other ships to harvest resources and ensure their own survival. Despite their assertions that the circumstances should exculpate their immoral actions, most of the crew is sentenced to prison. Gravity soon leaves with two now peaceful Trisolaran droplets to intercept Blue Space, which refuses to turn around after having been warned by Bronze Age what awaits them.

Cheng Xin wakes from hibernation. Her star, DX3906, has been discovered to have planets. The UN wants to buy it from her, but she won’t give up Yun Tianming’s gift. Instead, she gives them the planets and sells them the star’s energy while retaining ownership of the star itself. With the profits of the sale, Cheng Xin forms the company Halo Group. AA, the astronomer who discovered the planets, becomes Cheng Xin’s assistant and head of Halo.

Wallfacer Luo Ji has been named Swordholder: the person who holds sole responsibility for broadcasting the location of Trisolaris in the event of Trisolaran attack. Luo Ji therefore singlehandedly maintains deterrence, but he has become wildly unpopular—the public accuses him of mundicide because he caused a star and any of its orbiting planets to be destroyed to prove his dark forest theory. Cheng Xin is a popular candidate to replace Luo Ji as Swordholder. The public sees her as the savior-owner of a star to which humanity could potentially escape. Thomas Wade, who also hibernated, shoots Cheng Xin—planning to kill her to forward his own candidacy for Swordholder. AA realizes Wade’s treachery and saves Cheng Xin.

The Dark Forest Deterrence depends on the reputation of the Swordholder: Only someone who seems capable of broadcasting Trisolaris’s location and also dooming Earth can warn off Trisolaran conquest. Luo Ji’s unpredictability and stoic personality make him the perfect candidate; these traits also make his fellow humans, both hawks and doves, despise him.

As Cheng Xin recovers, she familiarizes herself with modern art and film. She is shocked to learn that Trisolarans now contribute to human culture, as deterrence has encouraged collaboration between the two civilizations.

In the Deterrence Era, Earth and Trisolaris share information. The Trisolarans instruct humanity in science, while humanity shares their art and culture. The Trisolarans hope that learning some of humanity’s creativity will eventually advance Trisolaran science. Human influence creates a large shift in Trisolaran authoritarian culture, which manifests in the way Trisolaran art represents humans.

AA tells Cheng Xin meet Sophon, an AI android created and controlled by the Trisolarans who is meant to help relations between the two worlds. Sophon, dressed in flowery clothes, elegantly welcomes Cheng Xin and AA into her home with the hours-long Way of Tea ceremony. As they speak, Sophon reflects on how fragile their worlds are and how all women must protect these delicate civilizations. Sophon endorses Cheng Xin as the next Swordholder.

The next day, six other Swordholder candidates, all men, ask Cheng Xin not to pursue the position because she will win if she does. They warn that the Swordholder must scare both Trisolaris and humanity; Cheng Xin’s public perception as an angel and her political inexperience make her a poor candidate.

A week later, when Cheng Xin goes to the UN to officially sign over the planets she owns, a woman gives Cheng Xin her baby to hold. As Cheng Xin cradles the child, she feels a maternal instinct to protect humanity. She announces her official candidacy for Swordholder.

Gravity finally catches up with Blue Space after 50 years. While Gravity can see how much fuel and resources Blue Space has with the help of a Trisolaran sophon, Blue Space knows nothing of Gravity. Escorted by Trisolaran droplets, Gravity is a major threat to Blue Space. However, during the final year of the pursuit, the link between the two ships severs as Blue Space passes through a sophon-blind region.

When sophons enter blind regions, they lose the ability to make contact and are lost forever. Trisolaris finds many blind spots close to their system and suspects that they are related to the dark forest theory. Trisolarans believe that intelligent beings have made these regions, since sophons pervade clearly uninhabited regions with no issue.

Seeing the droplets and remembering their destructive capabilities during the Doomsday Battle, Blue Space recognizes the futility of their flight and surrenders to Gravity. As Blue Space begins decelerating in preparation for docking and the crew of Gravity wakes from hibernation to prepare for the capture, odd things begin to happen. One man sees a crew member from Blue Space on Gravity, while another man wakes to find the wall to his neighbor’s cabin gone and her legs seemingly cut off; the neighbor is fine the next day. Guan Yifan, a civilian scholar aboard Gravity, complains of intense claustrophobia. He tells the ship’s psychiatrist that he dreamed of a wide open space and now waking life feels too close together. As they talk, an alarm sounds—the droplets are attacking.

Six months after being elected Swordholder, Cheng Xin descends 45 kilometers below the surface to relieve Luo Ji and actually take command of the deterrence system. The Swordholder has control over a broadcasting system that uses strong and long-ranging gravitation waves, which could reveal the location of Trisolaris and Earth, dooming both worlds.

Three antennas on Earth and the hull of Gravity possess the capability to send the gravitational wave transmission. The antennas on Earth are underground, but still vulnerable to Trisolaran droplet attack. Though Trisolaris promises that no droplets are left in the Solar System, humanity suspects Trisolaris of having hidden some. Therefore, given the droplets’ speed, the Swordholder will likely only get 10 minutes to flip the switch and activate the broadcast.

Ten minutes before the official transfer of duties, Cheng Xin watches Luo Ji stare at the wall of the underground bunker. He holds the switch in his hand, stoically facing down the Trisolarans, watched at all times by sophons that relay his image to their home world. When the transfer of power takes place, no one thanks Luo Ji and he is arrested for mundicide. He leaves in silence.

Moments after Cheng Xin becomes Swordholder, alarms blare. A screen in front of her announces that six Trisolaran droplets are heading at maximum speed toward Earth. As she watches the 10-minute countdown tick away, Cheng Xin decides that she cannot activate the switch and extinguish the history of humankind. She never truly believed this moment would happen; knowing this about her is why the Trisolarans attack. She throws the switch away as the droplets destroy all three Earth antennas.

Cheng Xin goes to the surface. AA is there, confused about what seemed to be an earthquake. In the distance, a mushroom cloud rises from the droplet’s impact against the nearby underground antenna.

Deterrence failed for many reasons. First, all three antennas were positioned on Earth, making a Trisolaran attack on them quick and effective. If more ships possessed antennas like Gravity, they could have spread out and slowed down the Trisolarans, giving the Swordholder more time to make a decision. However, more ships like Gravity were not built because of the immense cost, and because of fears that the ships could flee, turn rogue, and broadcast Earth’s location.

In the crater created by the droplet, Cheng Xin and AA find Sophon, now dressed in military clothing and armed with a katana. Sophon explains that Trisolaris hoped for Cheng Xin’s election to Swordholder and planned to attack as soon as the handover was complete. Sophon assures them that droplets also destroyed Gravity, though Sophon has no proof of this because of the sophon blind spot. Sophon opines that while Cheng Xin was a weak Swordholder, Thomas Wade, with his ruthlessness and perseverance, would have been perfect for the role. Sophon tells them to prepare to move to Australia.

Thirty-eight days later, Earth observes a new Trisolaran fleet passing through an interstellar dust cloud. Earth at first believes that it will take hundreds of years for the Trisolarans to reach Earth, but data dashes such hopes. Unlike the First Trisolaran Fleet, these ships can achieve light-speed and will be at Earth soon, though they must take time to decelerate. The Trisolarans do not stop or start light-speed near Trisolaris or Earth, which humans interpret to mean that the acceleration and deceleration poses a planetary threat.

Trisolaris’s technological jump to light-speed is due to one of two possibilities. The social changes human civilization brought might have encouraged them to shift away from their authoritarian society and value free thinking. Alternatively, one of their exploratory sophons could have discovered another, more technologically advanced world from which they learned.

The AI Sophon announces that the Second Trisolaran fleet will reach Earth in four years. In the meantime, humanity will have limited use of technology and will be forced to resettle in Australia and on Mars. Out of respect for Earth’s civilization, Trisolaris will not exterminate humanity, but rather take over the planet and then help humans colonize other parts of the Solar System.

When Sophon’s demands are not met, a droplet attacks cities in North America, Asia, and Europe, making the threat a reality. The Great Resettlement to Australia begins.

With billions coming to Australia, life is difficult and resources scarce. Political and social order soon deteriorates; refugees storm cities, only to be massacred by the Australian government. Soon, people abandon democracy for despotism. Cheng Xin and AA struggle to find a safety in the resettlement zone, where Cheng Xin is harassed until an Indigenous man named Elder Fraisse invites them into his house. Cheng Xin finds Thomas Wade, who warns her to leave.

Sophon gives humanity one year to resettle in Australia; all humans outside its borders will be hunted and killed. Sophon creates the Earth Security Force (ESF), a human brigade of the Trisolaran army. When Sophon’s deadline arrives a year later, the ESF murders people in faraway cities and bombs all sources of electricity in Australia. Cheng Xin wakes to these bombs and witnesses Sophon addressing the UN on TV. Sophon declares that the Great Resettlement is complete, that the Second Trisolaran Fleet will arrive in three months, and that humanity will now be defanged. Humans will no longer have access to electricity and will be forced to survive on limited food sources. Sophon acknowledges the difficulty of this, and suggests humans eat each other. This way, when the Trisolarans settle, only a small fraction of humanity will be left.

As the crowds around Cheng Xin descend into chaos, she is knocked down and suddenly goes blind. An ESF operative finds her and gives her a cellphone connected to Sophon. Sophon offers to save Cheng Xin, but Cheng Xin refuses, instead bargaining for AA and Fraisse’s lives. Cheng Xin is resigned to living out her fate in Australia as a consequence of her failure as Swordholder.

On Gravity, the droplet attack alarms suddenly cease. The captain of Gravity and his officers watch as the droplets miss both ships, go off course, and grow rusty. Suspecting a threat to the gravitation wave transmitter, the captain pushes the secret self-destruct button on his watch, but receives an error message. In a panic, he rushes to the gravitation wave transmitter command room to find marines from Blue Space everywhere.

Confused about what is happening, Gravity surrenders to Blue Space. The captain of Blue Space informs the crew of Gravity that another Trisolaran fleet is heading to Earth at the speed of light and that Earth’s deterrence system has been destroyed. The droplets that turned off course were going to destroy Gravity’s transmitter as well. After a crew-wide vote, a two-thirds majority agrees to activate the gravitational wave transmitter and reveal the location of Trisolaris (and the Solar System).

Cheng Xin listens in confusion as the calamity around her suddenly turns into cheering. A man tells Cheng Xin that everyone can return home. When she asks how this is possible, he tells her that Trisolaris received a broadcast from Gravity; now that the Solar System and Trisolaris are doomed, the Trisolarans are fleeing, their fleet altering course away from the Solar System.

Guan Yifan and others from Gravity learn from Blue Space scientists that the odd occurrences they’ve been experiencing are due to the ships passing through a giant four-dimensional fragment (the same kind of anomaly that allowed Helena to briefly believe she has magical powers during the Fall of Constantinople at the beginning of the novel). In this fragment, windows appear in which humans can enter four-dimensional space. When Guan Yifan explores four-dimensional space, he can see everything around him with a new depth, similar to the dream he had. In the fourth dimension, he can even touch the inside of objects, which explains how the crew of Blue Space attacked the droplets and boarded Gravity. Inside the four-dimensional fragment is a giant ring-shaped object; the scientists decide to send a team to explore it.

Guan Yifan and two others take a small ship on a risky trek through four-dimensional space to the ring-shaped object. They send the Rosetta System, a program containing instructions to learn human language, to the ring. The ring communicates back, explaining that it is a tomb and that the four-dimensional fragment is shrinking. It tells them that the “fish who dried the sea went onto land before they did this. They moved from one dark forest to another dark forest” (253). This cryptic explanation references another dark forest strike weapon, which can collapse an area into a lower dimension.

Blue Space and Gravity watch as the ring falls into three dimensional space, giving off a powerful burst of light and energy. Before continuing their journey, Blue Space and Gravity send a hibernation ark with some crew back to Earth to warn humanity of their discovery.