Heretic

After the fall of Calais, Thomas leads a band into Gascony and seizes the castle of Castillon d'Arbazon to draw out his cousin Guy. There he saves Genevieve, condemned to burn as a heretic. The choice wrecks his friendship with Robbie, who turns on him, and Thomas ends up excommunicated. Guy Vexille arrives hunting the Grail, and Thomas and Genevieve flee to a monastery, whose abbot Guy later murders. Thomas returns to Castillon and is besieged in the castle. The Black Death strikes both sides. In the final assault, Thomas kills Guy and forgives Robbie. Teaching Genevieve to read from his father's Bible, he finds the clue to the Grail's hiding place. He recovers the relic and throws it into the sea, sure it would only bring more death.

1. Behind the scenesA small war in the truce

   Per the author's site, the novel opens with the fall of Calais and most of it happens in the truce that followed. For Thomas there is no truce.

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2. Behind the scenesA different Spanish title

   In Spain, Edhasa published the book as El sitio de Calais, the third in its Arqueros del rey series.

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3. ReferenceThe plague is real

   The Black Death reached Europe in 1347 and killed a huge share of the population over the next few years. Cornwell puts Thomas right at its start.

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4. ReferenceThe Cathars

   The Vexilles' heretic past comes from the Cathars, dissident Christians in southern France crushed by the Church in the 13th century. Hence the title.

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