In this book, Bishop Loris decides that the Deryni Duke Morgan must be held accountable for his Deryni magic, so he threatens all of King Kelson's kingdom with interdiction (the refusal of sacramental services) until the King turns out his Duke.
In this second novel of her career, Katherine writes clean prose, clear characters, and comprehensible scenes.
Sadly, all the good traits of this novel are overwhelmed by its anemic plot and unfathomable characters. Chief of these unfathomable character is Bishop Loris, who insists on prosecuting Morgan for his sins, never mind the civil war he's about to instigate or the church crisis that he triggers. These never bother him. Despite his clearly well-developed intelligence, he pushes the kingdoms towards doom for the weakest of pretexts, ignoring all his peers, and ignoring all the rules which he so richly upholds.
Humans purportedly fear Deryni because "they are different." I think that's odd, because humans are right to fear anyone who can attack your mind, change your memories, wield vast deadly power, read minds, defeat all locks, talk mind-to-mind across vast distances, sense your presence remotely, and alter your emotions. The powers that the Deryni display in the book are truly intimidating, if not disturbing in their implications.
I counted five main plots in the books, most of which don't amount to much. In following so many threads, I felt like no thread got the time that it deserved. Some of the plot lines felt like filler.
In the end, I wound up skimming my way through the book. I don't feel that I lost any plot nuances.
If you like many descriptions, you're predisposed to like the work. Kurtz loves describing everything. If you don't like descriptions, the book feels extremely padded.