The Left Hand of Darkness is a science fiction novel written by Ursula K. Le Guin. It is set in a future where humans have made contact with an alien race known as the Gethenians, who have the ability to change their gender at will. The story follows Genly Ai, a human envoy sent to establish diplomatic relations with the Gethenians. As Genly navigates the cultural differences and political complexities of the Gethenian society, he grapples with his own biases and preconceptions. The Left Hand of Darkness is renowned for its exploration of gender and sexuality, as well as its thought-provoking examination of societal norms and prejudices.