Cixin Liu's trilogy-opening novel about first contact with aliens and the clandestine struggle with them over Earth's future, and its scientific progress in particular. Set against the backdrop of China's Cultural Revolution, a secret military prject sends signals into space in an attempt to make contact with aliens—and they succeed. An alien civilization on the brink of descruction captures the signal and plans to invade Earth. Now, on Earth, different camps start forming, planning to either welcome the superior beings and help them take over a world seen as corrupt, or fight against the invasion. The result is a science fiction masterpiece of enormous scope and vision.