Genly Ai misreads Estraven's loyalty
Genly Ai, sent alone to persuade Gethen to join the Ekumen, distrusts the Karhidish prime minister Estraven because he reads Estraven's reserve and shifting manner as feminine deviousness. Estraven is exiled for backing Ai's mission, then rescues him from an Orgota labor camp and hauls him across the Gobrin Ice on an 80-day sledge journey. Only on the ice does Ai see Estraven as a whole person rather than 'a man' or 'a woman', and by then Estraven has only weeks to live.
