Princess Eilonwy is the most important character of The Castle of Llyr. Following her reluctant departure from Caer Dallben, Eilonwy is sent to Dinas Rhydnant on the Isle of Mona to continue her upbringing as a princess and a young lady. Her own disagreement with the arrangement is equaled only by Taran’s unhappiness at his separation from her. However, even the Isle of Mona is not safe from the threats of Annuvin when Princess Eilonwy must face an old enemy as deadly and treacherous as Arawn, the Lord of Death.
Lloyd Alexander’s third volume in The Chronicles of Prydain does not deviate from the content or style of the previous two volumes in the series. On the contrary, the author still gives attention to Taran, who struggles not only with his own temperament but also with the new character of Prince Rhun, who is his rival for Eilonwy’s affection. Fflewddur Flam and Gurgi serve as Taran’s steadfast companions, as well as the disguised Prince Gwydion. But the author introduces many new characters, like the pathetic giant, Glew, and the rambunctious, gigantic feline named Llyan. A new villain is revealed in Magg, and he is not less malicious than Arawn himself. Danger threatens Eilonwy’s life this time more than any of the other characters, although the consequences of her kidnapping are serious for all Prydain.
As the author mentioned in his own introduction to the novel, The Castle of Llyr is more romantic than its predecessors. However, its plot is dominated by the constant war between good and evil. The definition of humanity is ever present. Taran perseveres in learning to master himself, with his growing sense of honor and his personal loyalties being incandescent qualities in themselves. The Castle of Llyr has abounding humor with the presence of Fflewddur despite its dark, serious tone. Intertwining wisdom, humane characters, the strong bonds of friendship, and romance, Alexander created another great work of fiction.
Original review: Part 3: Lloyd Alexander’s ‘The Chronicles of Prydain’, Examiner.com