In this sci-fi thriller, the first book of a trilogy, humans are divided into caste-like categories with the ruling "Golds" on top and the low-level "Reds" - essentially slaves - doing all the drudge work. Other color groups are artists, soldiers, law-enforcement personnel, pleasure givers, bureaucrats, and so on.
Darrow, a 16-year-old mine worker living in an underground colony on Mars, is a very low Red. The Reds - whose lives are generally short, hard, and hungry - are constantly bombarded with propaganda praising them for their help in terraforming Mars so that humans from an overpopulated Earth will have a place to live to in the future.
When Darrow and his young wife Eo run afoul of the law tragedy ensues and Darrow realizes that the Golds - concerned only with their own power and comfort - have been dishonest and manipulative. Encouraged by his dying wife Darrow becomes determined to get revenge and free the Reds. Helped by his uncle, Darrow falls in with a band of rebels who "transform" him to resemble a Gold. This allows Darrow to gain gain entrance into a selective academy that prepares Golds for the highest positions in society. This is no regular school however, and what follows is like a hyper version 'The Hunger Games'.
The academy students are divided into 'houses' - mentored by praetors - that battle each other until one house is the winner. The whittling process takes many months during which the students try to demonstrate their intelligence and battle prowess in hopes of getting job offers from the most prominent Gold families. The students are forced to perform horrific deeds, which some do reluctantly and others revel in. Alliances form and fall apart, cheating occurs, and not everyone is who they seem.
Darrow is smart and capable but seems to be thwarted every time he's about to achieve an important goal. Thus he must learn to be cleverer, sneakier, and more politically astute than his rivals. In the course of the story Darrow evolves from a complacent teen to a warrior determined to get justice for the Reds. I liked the book and look forward to reading the rest of the series.