Myrredith is a strong willed, independent woman, with the intelligence and compassion to rule her domain better than any man. Despite her stubbornness, she is married off to Sir Aonghas who wins her hand in a jousting tournament – a tourney that her true love Sir Hugh could not attend because he was stopping an invasion of the army of Gwyddea, at the battle of Sciula Tor.
Myrredith becomes Billy‘s patron after a chance meeting at The Valley’s Finest, an inn run by Billy’s adopted father, in the Valley of the Yew. Myrredith is quickly drawn to the charismatic Billy, when she senses in him something strangely familiar. Only much later in the story does she understand that it his resemblance to her late brother Rory and also Billy’s biological father, King William.
Myrredith’s sisterly affection towards Billy is enough for her to ask that he accompany her to her home near the coastal city of Dyven. It is on this fateful trip that Billy encounters a forest dragon and is saved by Sir Hugh, the King’s Champion (and Myrredith’s past love). This reunion of Myrredith and Hugh unearths feelings buried for years. As Hugh and Myrredith spend more time with each other, regaining the closeness of their youth, her husband Aonghas takes notice – a situation aggravated by the Spanish troubadour Don Miguel Scarosa. When they all travel to the royal wedding of Princess Kathryn and Prince Gaelyn in Nyraval, the love triangle is further cemented. Myrredith is eventually widowed, when Aonghas dies a heroic death.
In The Prince, Myrredith is captured at Cyndyn Hall by a new invasion of Gwddnies lead by Prince Hereweald (Gaelyn’s brother). During the occupation, Hereweald sentences Myrredith to death, only to fall in love with her. This creates a strange love triangle between Hugh, Myrredith and Hereweald. In the midst of the war, Hugh rescues Myrredith, with the help of some loyal friends, but it is not until the end of the book that Myrredith and Hugh are united as they should be – in marriage.