The Left Hand of Darkness is the story of Genly Ai, ambassador of an intergalactic confederacy known as the Ekumen, and his journey to the planet Winter. The human inhabitants of Winter are ambisexual, spending most of their time in an androgynous state and adopting male or female sexual characteristics during a monthly mating period. Genly's story explores Western conceptions of sex and gender, as well as the idea of androgyny.