The Left Hand of Darkness is a science fiction novel written by Ursula K. Le Guin. It is set on the planet of Gethen, where the inhabitants are androgynous and can change their gender at will. The story follows a human envoy who is sent to Gethen to establish diplomatic relations. Through his experiences, the novel explores themes of gender, sexuality, and the nature of humanity. The Left Hand of Darkness is a groundbreaking work that challenges traditional notions of gender and identity.