Author Liu Cixin Photo: Zachary Bako

Aliens are invading Earth, and there are two Chinese camps: one that welcomes the alien invasion and one that wants to fight it.

That is the story line of “The Three-Body Problem,” a science-fiction trilogy written by China’s Cixin Liu, the first book of which will hit American bookstores Nov. 11 in English translation.

The trilogy, which was awarded the Galaxy Award, China’s top honor for science fiction, has already sold more than a million copies in its original Chinese, making it the best-selling work in this genre in China in decades. It tells the story of a civilization in another solar system that is facing extinction and chooses to invade the Earth to save itself.

Mr. Liu explains that the “three-body problem” is a term borrowed from physics that involves two objects in space interacting in a predictable fashion, rotating around each other as a result of their gravitational pull. But when a third object is introduced, it makes their interaction more complicated.

The “three-body problem” points to the complexity of our environment, says Mr. Liu, a power-plant engineer who was born in 1963 and came of age during the tumultuous years of China’s Cultural Revolution, when most Western books were banned.

Nonetheless, the young Mr. Liu found and devoured translations of books such as “Journey to the Center of the Earth” and “Twenty Thousand Leagues Under the Sea,” which he found hidden under beds in his family’s home.

Though science fiction isn’t as popular in Chinese literature as it is in the West, Mr. Liu’s trilogy has found a sizable fan base, one even the author can’t explain.

“Perhaps it’s linked to the fact that Chinese society is industrializing rapidly. Chinese people are increasingly considering the world not from the perspective of their own nation, but from the perspective of all mankind,” he says. “More and more Chinese have begun to care about where we come from, where we are now and where we are going. And they have begun to care about the fate of our planet and the entire universe.”

Mr. Liu’s trilogy draws on his experience growing up during the Cultural Revolution, a decade when Mao Zedong sent radical youths rampaging through the country in a purge of Mao’s political opponents as well as any old principles. In a convulsion of ideological purity, they turned on their elders and those in authority—and eventually battled among themselves. A character in the book who was a victim of the turmoil comes to the aid of the aliens who have invaded Earth.

Mr. Liu says this period is used as backdrop to advance the narrative. “The story requires a person who has lost all hope for humanity. In all of mankind, only two things could do this. One was the Cultural Revolution, the other the Nazi holocaust.”

Huang Hailin, a college student in Wuhan, skipped class and took a 10-hour train to Beijing to attend a science-fiction award ceremony and fair over the weekend, where Mr. Liu, whom many fans call “Da Liu” or “Big Liu,” was in attendance.

“The Three-Body Trilogy has become a bible among Chinese sci-fi readers,” he said. “Everyone reads it.”

Mr. Huang also bought about 20 copies of the series and had them autographed by Cixin Liu and Ken Liu, the series’ American translator, at the event. “I’m really hoping the English version can be sold in China,” he said. “There will be many people who want to collect a copy.”

Liu Tianyuan, a college student also attending the ceremony in Beijing, said that when Mr. Liu’s trilogy came out, she felt there was finally a sci-fi book that could compete with, or even beat, U.S. books in the genre. “It made me proud of Chinese sci-fi,” she said.

Tor Books, a science-fiction fantasy publisher owned by Macmillan, is printing 15,000 copies of the first book in the trilogy, with the second book set to publish next summer. Ken Liu, himself an award winning sci-fi writer, says the trilogy’s first book is shorter than its sequels, but a reader can already get a sense of the grand tale to come.

“The story features mystery, intrigue, characters pitted against difficult problems they must overcome—and of course, some very interesting scientific speculation and philosophizing,” he says. “The series tries to tackle the biggest questions of existence, and the story it tells is an epic in every sense of the word.”

Liz Gorinsky, who edited the English translation of the “Three-Body Problem” at Tor Books, says Tor took an interest in the books because they came highly recommended from smart American and American-Chinese science-fiction writers. In addition to being “very different than anything you would expect from an American science-fiction novel,” she says, the translation offers readers an interesting cultural perspective.

“China is in the news a lot, but there aren’t many direct cultural exports being published as part of mainstream media,” Ms. Gorinsky says. “Obviously, you can’t get the Chinese cultural perspective from just one author, but there are relatively few opportunities like this to see what the modern Chinese social landscape is like,” she says.