Saba, Lugh and their younger sister Emmi live with their pa in Silverlake. Their mother died while giving birth to Emmi and Saba has never been able to forgive her sister. Tensions mount between Lugh and their pa as the family struggles to find enough water and food.
Then one day four men come on horseback, kill their father, and kidnap Lugh. Saba chases after them, but can't save her brother. She yells to him that she won't stop until she finds him. Now with only Saba and Emmi left, Saba must take over and watch out for her little sister. They head out to find Mercy, a family friend who their father said to go to if something happened to him. By the time they arrive they're exhausted, hungry, and thirsty.
Mercy agrees to take care of Emmi while Saba goes in search of her brother. Soon after Saba heads out Emmi finds her and insists on tagging along. The trail proves to be just as dangerous as Saba feared when they're both captured by some slave traders.
Saba is forced to be a cage fighter in Hopetown's arena. If any cage fighter loses three fights they have to walk the gauntlet and get beaten to death by the crowd. Determined to find her brother Saba stays alive and wins all of her fights. She becomes known as "The Angel of Death".
Meanwhile she makes allies among the other cage fighters and hatches a plan to escape. One of the friends she makes is a male cage fighter, Jack. The heartstone Mercy gave her to wear heats up whenever she's close to him. Even though Saba's plan for escape is pretty risky, she knows she has to get to Lugh, but can she do it, meet up with Emmi, and not get caught?