Content warning Discusses elements of the plot
We haven't read the other books in the trilogy. How to describe? Liu has a very pessimistic perception of humanity and the nature of the universe. Not only does it science what kind of beings might evolve in a three-body solar system, but he also engages the Fermi Paradox, a very pessimistic theory about intelligent life. Be prepared to deal with frustration and disappointment.
That said, it is an important book and should be read.