Death's End, the conclusion to Liu Cixin's celebrated Remembrance of Earth's Past trilogy, is a multi-layered and complex tale that moves through both time and space to tell an epic story with a breathtaking scope in a translation by Ken Liu that handles both the nuances of fairy tales and the specifics of mathematical speculation with transparent skill
The core narrative is centred on the brilliantly innovative scientist Cheng Xin, and its beginning unfolds concurrently with the early years of the Wallfacer project, which was the focus of the second novel of the trilogy. While Luo Ji develops his understanding of the sociology of interstellar relations - the Dark Forest theory, that advanced civilisations will both hide their own existence, and destroy any developing civilisations that may become a threat - and its defensive corollory, dark forest deterrence, the threat of revealing to the universe the wherabouts of the Trisolaris system - Cheng Xin's early work is in the outward-looking Staircase Program, an attempt to accelerate a probe to a sufficient fraction of lightspeed that it will meet the Trisolaris Fleet, carrying a unique cargo, the brain of a human volunteer.
Cheng enters hibernation after the probe is launched, and wakes in the era of dark forest deterrence, an uneasy truce period between Earth and Trisolaris brought about by Luo Ji's discovery of the dark forest principle. Luo Ji has become the Swordholder, the person who will bear responsibility of releasing the signal that will transmit to the universe both the Trisolarian location, and Earth's, should the Trisolarians attempt to conquer Earth.
In a way, Cheng Xin's life from this point becomes the story of Earth's struggle with the idea of the dark forest, a contest of love and compassion against fear and destruction. She becomes the Swordholder, but when the Trisolarians act, she proves unable to do what will ultimately destroy both worlds.
As Cheng moves through the centuries, and eventually the millenia, through both hibernation and a series of relativistic incidents, the human race struggles for survival, for a path through and out of the dark forest - and in the process, the reader is presented with a cornucopia of ideas, theories, and concepts about everything from stellar mechanics to relativistic travel to multi-dimensional geometry, and all of it in the service of story.
Ultimately, the utter sterility and inevitable destructiveness of the dark forest is revealed, but Cheng, present even at the end of all things, manages to personify love and hope, sending a 'message in a bottle' that may alter the very nature of the universe to follow.
A stunning conclusion to a work of vast scope and intricate design, a sciencefictional masterpiece.