When I first heard this book was coming out, I had heard that it was an urban fantasy with vampires. Then I heard it was an urban fantasy with werewolves. I was NOT expecting a science fiction post-apocalyptic western sports story!!!
This is nothing whatsoever like the other books by Carey that I have read. It is not alternate Earth historical fantasy like her Kushiel books. It is not epic high fantasy with a twist like her Sundering duology. The only thing it has in common with those other books is that it is largely character driven.
Following a huge pandemic of influenza in Mexico, the US government seals the border area off. The residents have a choice to move north into the US or to stay where they are and become citizens of no country, cut off from the world save for the US military and under tight military control and rule. If they stay, there is no way out and no escape.
The town of Santa Olivia becomes part of this no man's land - though the local base commander has promised a pass out for any local who can beat his boxing champion.
Into this odd situation, the main character is born -a little girl born of a local woman and an escaped soldier who has been genetically engineered for strength, speed, stamina, and enhanced senses. With the support of her friends at the the orphanage run by the local church, she takes on the persona of the local patron saint, Santa Olivia, to strike some blows for justice and freedom - which angers the military and threatens not only her life, but those of her friends and supporters as well.
While this book was nothing like what I was expecting, I did end up enjoying it greatly, and I hope that Carey will write other science fiction novels someday.