At the time when the kingdom of Dagda extended over the hills of Ireland, Angus, an elven prince, fell in love in unusual circumstances ...
One night, while he slept, Angus dreamed that he felt the freshness of silk and breathed the smell of the flowers of an apple tree. He saw a light appear near his bed that took the form of a woman. This woman, Caer, called Angus by name and played a bewitching melody with a lute. Then, while the last music notes went out, disappeared. Since then Angus did not stop looking for her throughout the kingdom.
Finally, one day he found her, but Caer lived a year low as a swan and another year low as a human. The love was so strong that Angus decided to become a swan so he could live with his beloved Caer.