Imagine the universe as a forest, patrolled by numberless and nameless predators. In this forest, stealth is survival - any civilisation that reveals its location is prey. Earth has. And the others are on the way. The Trisolarian fleet has left their homeworld and will arrive...in four centuries' time. But the sophons, their extra-dimensional emissaries, are already here and have infiltrated human society and and de-railed scientific progress. Only the individual human mind remains immune to the sophons. This is the motivation for the Wallfacer Project, a last-ditch defence that grants four individuals almost absolute power to design secret strategies, hidden through deceit and misdirection from Earth and Trisolaris alike. Three of the Wallfacers are influential statesmen and scientists, but the fourth is a total unknown. Luo Ji, an unambitious Chinese astronomer, is baffled by his new status. All he knows is that he's the one Wallfacer that Trisolaris wants dead.