In The Three-Body Problem, the opening volume in Cixin Liu’s magnificent trilogy, Remembrance of Earth’s Past, Earth’s population found itself facing an unprecedented threat. Trisolarans, technically advanced inhabitants of a dying planet, have focused their attention on Earth, and are determined to make it their new home. As this astonishing second volume opens, the Trisolarian fleet has just been launched. Their journey will take more than 400 years to complete, but they are on their way. And that fact changes everything.

In an epic narrative spanning centuries, The Dark Forest examines the effects of a remote but very real threat on the citizens of Earth, effects that are at once spiritual, psychological, and pragmatic. Science and technology make concerted efforts to rise to the occasion, but encounter a single, insurmountable problem. The Trisolarans have littered the earth with sub-atomic particles known as “sophons” that have two functions. They place unbreakable limits on human technological development, and they reveal every secret strategy and plan to the invading forces. Faced with an obstacle they cannot overcome, the leaders of Earth develop a desperate, last-ditch plan called The Wallfacer Project, in which four individuals are given unlimited resources to develop—in absolute secrecy—a feasible defense against an immensely superior enemy. One of these four—an insignificant astronomer named Luo Ji—may hold the key to human survival in the dark, predatory forest of the universe.