Summary
Genly Ai, a human envoy from an interstellar alliance called the Ekumen, is sent to the planet Gethen to persuade its inhabitants to join the coalition. Gethen is a world locked in a permanent ice age, where the people are ambisexual—they have no fixed gender and only express sexual characteristics during a monthly cycle called “kemmer.” Ai struggles to understand Gethenian politics and culture, initially failing to grasp the complexity of his allies and enemies.
As Ai travels between the rival nations of Karhide and Orgoreyn, his mission becomes dangerous, leading to his imprisonment and subsequent escape. He forms a deep, transformative bond with Estraven, a disgraced politician who guides him across a lethal ice shelf to safety. Through this journey and the intense physical and emotional trials they share, Ai overcomes his deep-seated prejudices, ultimately seeing the Gethenians as fully human and succeeding in his diplomatic mission.