“I’ll make my report as if I told a story, for I was taught as a child on my homeworld that Truth is a matter of the imagination.” Le Guin, Ursula K. The Left Hand of Darkness, Chapter 1, p.1.
The story follows Genly Ai, an anthropologist from Terra and ‘first contact’ envoy to the harsh and inhospitable icebound planet Gethen (known by the Ekumen as planet Winter) in a mission to persuade the Gethenians, the ambisexual peoples of Gethen, to join the Ekumen’s confederation of planets. Landing in the kingdom of Karhide, one of the two major nations on Gethen, Genly Ai develops diplomatic ties with Therem Harth rem ir Estraven, a Karhide statesperson. However, when Estraven falls victim of a political power play labelling him a traitor and condemning him to a lifelong exile, Genly Ai realises that, because of his involvement with Estraven, he is also in danger and relocates himself in Orgoryen, a rival nation to Karhide, where he reunites with Estraven and with whom he will begin a journey towards understanding, acceptance and trust.
Ursula K. Le Guin's The Left Hand of Darkness isn't like any other science-fiction novels in the sense that it has no interest in diving into political intrigues, advanced technologies or even physical conflicts as this novel focuses mostly on the philosophical and emotional growth of its characters, and its readers too, by asking the following question: what if gender was not fixed but serially mutable?
"The king was pregnant." Le Guin, Ursula K. The Left Hand of Darkness, Chapter 8, p.99.
As said in the first paragraph, the Gethenians are ambisexual peoples which means they are neither/both male nor/and female except during their three-day period of kemmer when they become sexually active as either male or female, without a say in the matter, leading to each Gethenian being a mother and a father at some point in their lives. This is in contrast with Genly Ai, the human envoy from Terra, who, just like any other humans, possesses one unchanging gender which, for the Gethenian is perceived as a biological anomaly or a perversion as, from their point of view, Genly appears to be in a perpetual kemmering state. The Gethenians' wholeness is opposed to Genly Ai's view of the male/female duality inherited from his native homeworld and which limits his understanding of the Gethenian peoples and culture while Estraven struggles to fully comprehend Genly as well.
“And I saw then again, and for good, what I had always been afraid to see, and had pretended not to see in him: that he was a woman as well as a man. Any need to explain the sources of that fear vanished with the fear; what I was left with was, at last, acceptance of him as he was. Until then I had rejected him, refused him his own reality.” Le Guin, Ursula K. The Left Hand of Darkness, Chapter 18, p.248.
Ursula K. Le Guin's novel is about the beautifully captivating inner journey of Genly and Estraven, two compelling, flawed and deeply human characters who learn to let go of their fear of one another, trust each other and accept each other for who they are in all their complexities and simplicity, in all their similarities and differences forming unbreakable bonds of love and friendship.
Le Guin, Ursula K. The Left Hand of Darkness, London, Gollancz, 1969 (this edition: 2018).