The allure of glorious lost causes inspires a tale set in 1242 amid the doomed heresy-fueled Occitan resistance to the French monarchy and the Church. Cathar commoner Raimon and Catholic noble Yolanda, rapt in their budding romance, care little for politics and religion. They share a devotion to their homeland, its songs, dances and legends, most especially the stories of the holy Blue Flame, destined to protect Languedoc. But the times plunge them headlong into a tightening net of intrigue, inquisition and betrayal, and both will have to decide whether their loyalty belongs to their people or to each other. The impeccably researched details reveal a deep appreciation for the region and its culture. Indeed, the narrator is the countryside itself, a stylistic choice that casts an oddly distancing effect upon the unfolding drama. The main characters bear the burden of representing their respective “sides,” leaving enlivening personality quirks to the various secondary personages. Even if too many improbable coincidences drive the plot, and the conclusion is an obvious setup for the sequel, it is unlikely that fans of medieval adventure will mind. (Historical fiction. 12 & up)