Liu Cixin’s Dark Forest is the direct sequel to the highly imaginative Three Body Problem. Set directly after the event of the Three Body Problem, this book chronicles humanity’s effort in addressing the unfolding events at the conclusion of the first book.
(For those who haven’t read the first book, please stop reading now as I will go into plot details of the Three Body Problem).
This book, though part of the same series, reads very differently from the first book. While the Three Body Problem is by no means a “small” story, the scope of Dark Forest is epic in comparison and spans a longer time span.
Earth has been put on warning. A fleet of highly advanced Trisolaran space fleet is on route to invade the planet. All higher forms of quantum research have hit a brick wall due to the sophons introduced in the first book. Due to this, scientific progress has been halted at atomic age. Humanity, faced with a common external existential threat, have to make difficult decisions which will have major ramifications on life quality, economics and governance.
While this book still has some fantastic applications of scientific advancement in a futuristic setting (especially towards the second half of the book), this story is more personal and philosophical. Unlike the first book where the characters are there to deliver exposition dialogue to move the story forward, we get to go into the heads of protagonists like Luo Ji, an womanizing astronomer and Zhang Beihai, a political commissar in the Chinese space force.
Luo Ji is chosen as a Wallfacer, one of four people who had been tasked by the UN to come up with a plan to save humanity. As the Trisolarans are incapable of deceit, the Wallfacers’ task is to come up with cunning strategies to subvert and defeat the invading force. At their disposal is almost absolute power and the entire resource of the world. Meanwhile Zhang Beihai, tasked with building a space force, is primarily concerned with “defeatism” and “escapism” among his troops because in war, the mental state of mind of the soldiers is of utmost importance.
The Dark Forest explores themes about humanity when faced with its greatest existential threat. Faced with an unknown powerful enemy that is more scientifically advanced, the book tries to answer a very simple question: can humanity put aside its petty differences and work together to stave off an impending attack? And if we can overcome the first step, how are we going to do it considering that our advancement in science and technology are so far behind the Trisolarans?
The book goes off in a few tangents, following the lead characters as they progress through Crisis Era, the years after the discovery of the Trisolaran’s plans. The characters’ plans and motivations are laid out for the reader and followed through to the end, some leading down to various dark rabbit holes of hopelessness and despair.
Sometimes, Liu Cixin created conveniently contrived scenes to illustrate his points and his stories read like dialogues between Greek philosophers. While other times, the scenes are awe-inspiringly good (from a traditional science fiction point-of-view). Regardless of which they are, as a collection, they are integrated and together they pack an emotional and intellectual punch to the reader.
I would recommend this highly bold and impressive follow-up to the Three Body Problem.