Breaking Down the Entire Confusing ‘The Three-Body Problem’ Book Series

Editor’s Note: The following contains spoilers for all three books of the Remembrance of Earth’s Past trilogy.

The Big Picture

• The Three-Body Problem
  books, based on Liu Cixin’s trilogy, follows a planned alien invasion of Earth.
• The second book,
  The Dark Forest
  , shifts focus to the Wallfacer program and a more compelling protagonist.
• Death’s End
  expands the trilogy to a galactic scale, revealing the collapse of dimensions and humanity’s survival.

The first season of Netlfix’ long-anticipated 3 Body Problem finally debuts this week, with a simultaneous release of all episodes. The sci-fi epic, co-created by Game of Thrones showrunners David Benioff, D.B. Weiss, and Alexander Woo, is an adaptation of Liu Cixin‘s instant-classic trilogy of novels known as the Remembrance of Earth’s Past trilogy. The novels, originally published in China, and translated into English by Ken Liu, have been wildly popular, and critically successful.

The first book in the series, The Three-Body Problem, won a Hugo award, and boasts a cover blurb from none other than former US President, current Netflix producing partner, and potential future Wallfacer, Barack Obama, who (though he turned down a cameo appearance) calls the books “wildly imaginative.” They are! Liu’s novels, which tell the epic story of a planned invasion of Earth’s solar system by a more scientifically advanced species known as the Trisolarans, break a lot of story-telling rules. While you’re reading these books, it genuinely starts to feel like anything could happen.

Keep reading for a spoiler-filled primer (or refresher) on what happens in all three books of Liu Cixin’s Remembrance of Earth’s Past trilogy.

‘The Three-Body Problem’ Kicks Off With a Decision That Changes Humanity Forever

The Three-Body Problem opens the trilogy with a story set in Earth’s past – specifically, during the political chaos, violence and paranoia of the period in Chinese history known as the Cultural Revolution. Student Ye Wenjie (played by Zine Tseng) witnesses her father, a physics professor, tortured to death by members of the zealous Red Guard for being a suspected “counter-revolutionary.” In chapters dispersed throughout the book, we learn the rest of her story. Ye, herself an astrophysicist, is assigned to a backwater science installation as a form of social exile. There, she works on a project meant to try and establish communication with extraterrestrial races using radio waves. Ye figures out a way to amplify the range of the installation’s equipment, and becomes the first human to communicate with an alien – specifically, with an alien of the species referred to in the books as Trisolarans.

Fortunately, the Trisolaran that Ye speaks with is a pacifist, who warns her that the rest of his race are violent and dangerous. If she ever sends another message through the stars, the Trisolarans will pinpoint Earth’s location and come conquer the planet. In other words, “DO NOT ANSWER!” However, Ye’s experiences have soured her on her own species, and she sees the warning as an opportunity. She sends back an invitation for the Trisolarans to come, and offers to help them conquer the planet. She tells them, “Our civilization is no longer capable of solving its own problems. We need your force to intervene.”

In ‘The Three-Body Problem,’ Humanity Learns About the Trisolarans

The primary storyline of The Three-Body Problem is set in the present day, where Wang Miao, a scientist who specializes in nano-technology is recruited to help investigate the recent rash of mysterious suicides in the scientific community. Supposedly, this is caused by the sudden change in behavior of sub-atomic particles: physics no longer works. At the same time, Wang begins hallucinating a very vivid countdown, as if projected onto the inside of his eyelids.

The mysteries continue to add up when Wang’s investigation leads to an underground community of players who participate in an impossibly sophisticated virtual reality MMORPGcalled Three Body, set on an alien planet. (The book contains many chapters set inside the world of this extremely bizarre VR game.) The planet of Three Body is characterized by periods of stable climate, interspersed with random periods of climate apocalypse – extreme heat, extreme cold, loss of gravity. The goal of the game is to figure out how to predict these periods of unstable climate.

With the help of badass cop Da Shi (played in the show by Benedict Wong), Wang eventually gets to the bottom of all of these mysteries. The solution to the VR game’s overarching puzzle is that the planet orbits three stars. The “three-body problem” is a real question in physics, concerning the extreme difficulty of mapping out the orbital path of a planet in a system of three stars. Unfortunately, the Trisolarans live on such a planet, hence the name. The Trisolarans live in a world where unpredictable extreme swings in climate and gravity are a part of life. Now that they have learned about Earth, they are coming here to conquer our planet in order to find a better place to live.

The Trisolarans Are Coming But the Invasion Has Already Begun

The Three Body game was devised by the Earth-Trisolaris Organization (ETO), a group of humans that aim to help the Trisolarans conquer earth. They are led by a now-old Ye Wenjie (now played by Rosalind Chao) and idealistic oil scion Mike Evans (Jonathan Pryce). Using Wang’s nano-fibers, a coalition of Earth governments set a gruesome trap for the ETO. As Judgment Day, the ship on which the ETO is headquartered, sails through the Panama Canal, a mesh of invisible yet ultra-strong nano-fiber is strung up in their path, slicing the ship and all aboard into ribbons.

The data recovered from the ETO’s computers reveals that, while the Trisolaran invasion fleet is coming, it will not arrive for 450 years. However, they have been able to send super-advanced devices known as Sophons that are already here. Sophons appear to be the size of protons, however, they are actually enfolded eleven-dimensional shapes of incredible complexity. These particles are able to communicate instantaneously with the Trisolaran fleet, and cause much mischief on Earth in the meantime. They’re able to halt any major advancement in physics by disrupting all of our experiments (the sci-fi equivalent of shouting random numbers while someone is trying to count their stack). They are also responsible for the hallucinated countdowns, which they are able to literally write on human eyeballs using, essentially, Sophon skywriting.

That’s where book one ends! Humans are screwed. The Trisolarans send the insulting message to earth “You’re bugs!” But the last word belongs to Ye Wenjie: “sunset for humanity.”

In the Second Book, ‘The Dark Forest,’ the Humans Strike Back

The Dark Forest is the optimistic middle entry in the Earth’s Past trilogy. The plot is far more unified, and doesn’t contain long chapters set inside a video game. Instead of Wang Miao, The Dark Forest shifts focus to the more compelling Luo Ji. The book picks up a few decades after The Three-Body Problem leaves off. Trisolaran Sophons are still among us, preventing our scientific advancement, and spying on our every move.

Humanity’s answer is the Wallfacer program. Wallfacers are four extraordinary humans, hand-selected by the UN. Each Wallfacer will devise plans to save humanity from the Trisolaran invasion. The Wallfacers wlll share their plans with no one, since the only place that Sophon surveillance cannot reach is the inside of a human mind. These individuals will be trusted with unlimited resources to set their plan into motion with a carte blanche to do whatever they want withoutt being questioned by anyone. The four selected Wallfacers are three brilliant minds from the worlds of politics and science, and one relatively ordinary guy, an obscure philospher named Luo Ji.

‘The Dark Forest’ Puts the Future of Humanity on Luo Ji’s Shoulders

Luo Ji does not understand why he’s been chosen, and abuses the power that comes with being a Wallfacer to create a perfect life for himself. Meanwhile, the other Wallfacers are each secretly assigned their own personal “Wallbreaker” from among the humans that are still loyal to the Trisolarans. Each Wallbreaker studies their subject’s every move, in order to deduce what their plan is. One by one, as the Wallfacers fail, Luo Ji continues to enjoy himself, getting married to the perfect wife, starting a family with her, and living an idealized life with the power he has as a Wallfacer. .

But the tables are turned when his wife rebels against his apathy. To motivate Luo Ji to actually confront the Trisolarans, she puts herself and their daughter into cryogenic hibernation, only to be awakened when the Trisolaran fleet arrives. Forced to accept his destiny, Luo Ji learns that he was selected as a Wallfacer because he is the only human the Trisolarans have tried to have assassinated. But no one knows why. Eventually, Luo Ji has a sudden epiphany: he had once had a brief conversation with Ye Wenjie, who knew the Trisolarans well, and she secretly hinted to him, without quite spelling it out, the Trisolarans’ achilles heel. After this realization, Luo Ji sends cryptic instructions to broadcast the coordinates of a distant star into the universe, and goes into cryogenic sleep for 200 years.

A Time Jump Into the Future Reveals Luo Ji’s Plan and Potential Peace

When Luo Ji wakes up to learn the results of his strange experiment, he finds that the Wallfacer program has been abandoned. Humanity has, instead, built a massive military space fleet that they believe will stand up to the Trisolarans. This confidence is quickly shattered with the arrival of the Trisolaran’s first probe — a metal “droplet” shaped orb — which looks harmless but proves to have a deadly skill set reminiscent of the deadly Sentinels of the horror franchise Phantasm.The Trisolaran probes rip the human fleet to shreds, with only a few ships fleeing into the darkness of the universe.

Thankfully, Luo Ji’s Wallfacer plan has actually revealed an important detail. Luo Ji has discovered the nature of the galaxy. With the potential of so many scientifically advanced civilizations, he likens space to a “Dark Forest.” Every species must stay hidden in this jungle full of possible predators. As soon as any species’ home star-system is known, it will be destroyed, out of an abundance of caution, by a more advanced species. (The Dark Forest theory is a real-world theory, but not on that is taken all that seriously.)

This is proven correct when the random star that Luo Ji broadcasted about is mysteriously destroyed. This suggests that another, more powerful civilzation we haven’t even heard of is also out there and could do the same to any other civilization they see as a threat. Thus, humans can keep the Trisolaran threat at bay by threatening to broadcast the coordinates of both Earth and Trisolaris across the galaxy, which would cause both planets to also be destroyed. This pact of mutually-assured destruction evens the playing field, and leads to a brief peace between Earth and Trisolaris.

‘Death’s End’ Sees the Story Move to a Galactic Scale

Death’s End expands the scope of the trilogy to a galactic scale. The feeling of reading this last book is like watching the iconic and trippy Star Gate finale sequence of 2001, A Space Odyssey… but nodding along in perfect understanding. The story begins during a period concurrent with the events of The Dark Forest, before the Trisolaran truce. Cheng Xin, is an engineer working on a project to launch a probe at the Trisolarans, despite being locked off from the scientific advancements necessary to achieve near-light speed travel. They come up with the idea of launching a single human brain into the galaxy using a series of nuclear blasts. The brain they use is of Cheng Xin’s dying friend Yun Tianming, who is in love with her. The hope is that when the Trisolarans find the brain, they could use it to clone a full human, who can then act as a spy…

By this point, Luo Ji has been Earth’s designated “Swordholder” for many years. The Swordholder is the person who holds their finger on the button that will broadcast the coordinates of Earth and Trisolaris, assuring the destruction of both. They have to be credibly willing to do this if the Trisolarans break the truce. However, Luo Ji is now quite old and retiring. Humanity chooses Cheng Xin as his replacement. This decision is contextualized as a result of humanity having grown soft and “feminine” during the peace earned for them by Luo Ji’s toughness, and is Exhibit A when the case is made that the trilogy exhibits sexism.

The Trisolarans immediately intuit that Cheng Xin, unlike Luo Ji, will not be willing to push the button that will doom Earth. They launch their “droplet” probes on Earth’s defenses, disabling its ability to broadcast beyond its own solar system. They’re correct to call Cheng Xin’s bluff. She pointedly decides not to push the mutually assured destruction button. The Trisolarans briefly achieve their dream of enslaving the human race, and relocate all humans to Australia while the planet is prepped to be the Trisolaran’s new home.

But, in deep space, two of Earth’s remaining ships, Gravity and Blue Harvest, which fled the solar system after the events of The Dark Forest, are able to get the upper hand on the pair of Trisolaran “droplets” sent to destroy them, by accessing fourth-dimensional space. The crew then fulfills Earth’s deadly promise by broadcasting its coordinates, along with those of Trisolaris, out into the “Dark Forest.” Soon thereafter, Trisolaris is destroyed by a mysterious third species, that fires a projectile into one of its suns. The Trisolarans abandon the invasion of Earth, which they expect to eventually be similarly destroyed by another race of aliens as per the “Dark Forest” theory. After all of this drama, we never even meet a Trisolaran!

Ten Dimensions? Changing the Speed of Light? ‘Death’s End’ Goes There

It is revealed that the Trisolarans did, indeed, reconstitute Yun Tianming from his space-drifting brain, and he is allowed to communicate with Cheng Xin, so long as he doesn’t share any scientific secrets. From across the universe, Yun Tianming tells Cheng Xin three twisted fairy tales, each encoding a secret message explaining how Earth can use science to escape sharing Trisolaris’ doom. However, these messages are not heeded. Instead, humanity relocates entirely into the shadow of Jupiter, where they hope to survive the eventual explosion of Earth’s sun.

Unfortunately, humans have underestimated the deadliness of the universe. In fact, what we perceive as the universe’s natural, three-dimensional state, is actually the result of eons of degradation resulting from “Dark Forest” warfare. The universe originally possessed ten dimensions, but over time these dimensions were collapsed as a result of interspecies warfare. Sound crazy? The practice is soon demonstrated to humanity in a definitive fashion. An alien species discovers our solar system and casually decides to destroy it. Realizing that humans can hide from conventional star-destroying weapons behind Jupiter, they launch a weapon that collapses the solar system from three dimensions to two. This flattening of the solar system is described by Liu in horrifying detail.

Cheng Xin watches the collapse of the solar system from just outside Pluto, where an elderly Luo Ji maintains an earth museum. Then, she and her assistant AA flee the solar system in humanity’s only light speed vessel, hoping to finally reconnect with Yun Tianming. However, those expecting some kind of romantic reconnection will be disappointed. Just as Cheng and Yun are about to reconnect on a distant planet, a time dilation accident transports Cheng Xin millions of years into the future, long after Yun and AA have died. Instead, she reconnects with Guan Yifan, a human from the ship Blue Harvest, who tells her that his band of humans has colonized the universe.

The two of them access a “pocket universe” that allows them to exist outside of time, where they wait until the final death and rebirth of the universe. Learning that humans have survived until the end of time, Cheng Xin and Guan Yifan leave a message in a bottle for the inhabitants of the universe about to be reborn.

How Can Netflix Adapt All of These Concepts Into a TV Show?

Higher dimensions can be imagined metaphorically, and have been depicted, of a sort, in movies such as Christopher Nolan’s Interstellar. Season 1 of 3 Body Problem is already pulling from characters and events that happen in the latter two books, but it will certainly take several seasons to reach some of the trilogy’s most exciting ideas. With so much to address, it only makes sense that Benioff, Weiss, and Woo are already plannng a Season 2.

3 Body Problem is available to stream on Netflix in the U.S.