Helen of Troy refuge with Leda. The swan gained her affection, and the two mated. Leda then produced an egg, from which Helen emerged. The First Vatican Mythographer introduces the notion that two eggs came from the union: one containing Castor and Pollux; one with Helen and Clytemnestra. Nevertheless, the same author earlier states that Helen, Castor and Pollux were produced from a single egg. Pseudo-Apollodorus states that Leda had intercourse with both Zeus and Tyndareus the night she conceived Helen. On the other hand, in the "Cypria", part of the Epic Cycle, Helen was the daughter of Zeus and the goddess Nemesis.
Leda and the Swan foundation myth in the Canadian futuristic thriller television series "Orphan Black" which aired over 5 seasons from 2013 to 2017. A corporation uses genetic engineering to create a series of female clones (Leda) and a series of male clones (Castor) who are also brothers and sisters clones as they derive from one mother who is a chimera with male and female genomes. The award-winning show addresses issues of the modern science of genetics, corporate greed, the ethics of human cloning, human longevity and the nature of individuality. Actress Tatiana Maslany won an Emmy award for her portrayal of all Leda