The Left Hand of Darkness is a science fiction novel by U.S. writer Ursula K. Le Guin. Published in 1969, it became immensely popular, and established Le Guin's status as a major author of science fiction. The novel is set in the fictional Hainish universe as part of the Hainish Cycle, a series of novels and short stories by Le Guin, which she introduced in the 1964 short story "The Dowry of Angyar". It was fourth in sequence of writing among the Hainish novels, preceded by City of Illusions, and followed by The Word for World Is Forest.
The novel follows the story of Genly Ai, a human native of Terra, who is sent to the planet of Gethen as an envoy of the Ekumen, a loose confederation of planets. Ai's mission is to persuade the nations of Gethen to join the Ekumen, but he is stymied by a lack of understanding of their culture. Individuals on Gethen are ambisexual, with no fixed sex; this has a strong influence on the culture of the planet, and creates a barrier of understanding for A