In Tourtoirac, Périgord, Isabelle Maurin, newly crowned Queen of Araucania, is found decapitated in the château she had just inherited. Emma Lambert, a young police lieutenant from Bordeaux, joins Sacha Besson, a local gendarme, to investigate. Emma, a transgender woman, conceals that she is the daughter of Julie Dupuy, the village doctor and mayor, with whom relations soured after her transition. As more murders point to the contested legacy of the 19th-century Kingdom of Araucania, Emma and Sacha must navigate a tangle of hidden identities, buried secrets, and dangerous ambitions—while confronting their own growing attraction.