A young woman's destiny is intertwined with the fate of a magical kingdom. Rhiannon, a princess of Dyfed, finds herself at the center of a prophecy that foretells both her rise to power and the potential downfall of her people. She must navigate treacherous political landscapes and confront ancient magical forces that seek to control her fate and exploit her unique connection to the land. The narrative unfolds through a blend of epic scope and intimate character focus, exploring themes of love, loss, and the burden of leadership.

Evangeline Walton's 'The Song of Rhiannon' is widely recognized as a significant contribution to modern fantasy literature, particularly within the Arthurian and mythological subgenres. Critics often praise Walton's lyrical prose and her ability to breathe new life into ancient Welsh legends. The novel is lauded for its faithful yet imaginative adaptation of the Mabinogion source material, offering a rich and immersive experience for readers. Its enduring appeal lies in its complex protagonist and its deep exploration of mythic themes, solidifying its place as a classic of the genre.