The City Without End. To See the Sun, #2

In the City Without End, level is everything. The overcity is bright and glittering, the realm of the First Families. As a dutiful son and heir, Cato spends his days crafting the contracts that bind citizens together-but by night, he works to undermine the corrupt system. When his activities come under question, he scrambles to cover his tracks. Then his family arranges a new marriage for him, and Cato must look deeper than he ever has into the society into which he was born.
Price, the hidden son of a First Family, took refuge in the dark undercity twenty years ago after leaving his family under a shroud of mystery. The only thing that could draw him back is the disappearance of his sister, and the fact that his family has betrothed him to the Prince of Contracts in her place. This so-called prince represents everything that's wrong with the city. But if he wants to keep his place and find his sister, he has to go along with his family's plans.
What begins as duty becomes more as Cato and Price realize they're not so different-and that someone wants them dead. Between dodging attempts on their lives and trying to find Price's sister, they must work together if they want a chance at humanizing the City Without End.