A Sorrow Fierce and Falling (Kingdom on Fire, Book Three)

Henrietta nervously awaits her marriage to Blackwood, but when the ritual to become his bride reveals a dark secret, she realizes that Sorrow-Fell is not a safe haven. Convincing the sorcerers of this is not easy. So with Maria, the true chosen one, and Magnus, the young man who stole her heart, at her side, Henrietta plots a journey straight into the enemy's lair. Some will live. Some will die.