When courage came to call

When their island city, Zamascus, is bombed and overrun by soldiers, thirteen-year-old Imm and his twin brother, Saxon, have to survive by their wits. They find two other children who have survived, and the four meet a charismatic man called Knight who is gathering children and training them to undertake missions within the city to win back Zamascus. Over time Imm becomes suspicious of Knight, wondering who he is, who he's really working for, and why Saxon can't see beyond Knight's promises of power and action and revenge. Imm must make a difficult decision in order to save himself and save his city.