The incestuous affair between the writer Anaïs Nin and her father, the pianist-composer Joaquín Nin, is well documented in the volume of her unexpurgated diary published under the title Incest. What has been missing from that account is Joaquín's point of view. Reunited: The Correspondence of Anaïs and Joaquín Nin, 1933–1940 presents more than one hundred intimate communications between these two artistic geniuses, revealing not only the dynamics of their complex relationship but also why Anaïs spent her life in a never-ending battle to feel loved, appreciated, and understood.

Reunited collects the correspondence between Anaïs and Joaquín just before, during, and after the affair, which commenced in 1933, twenty years after he had abandoned his ten-year-old daughter and the rest of his family. These letters were long believed to have been destroyed and lost to history. In 2006, however, a folder containing Joaquín's original letters to his daughter was discovered in Anaïs's Los Angeles home, along with a second folder of her letters to him. Together, these letters tell the story of an absent father's attempt to reconnect with his adult daughter and how that rapprochement quickly turned into an illicit sexual relationship.