The premise is in the year 2050, the United States has become an overcrowded slum full of refugees who are treated like garbage by the rich, a corrupt police force, and a media obsessed society that routinely pumps out fake news from independent bloggers as well as corporate sponsors. So, the big change is the United States actually taking in people suffering in other countries rather than turning them away at the gate.
The protagonist, Terri Pastuzka, is a recently divorced lesbian police officer who works the beat of Los Angeles. It is a thankless task and the author does an excellent job of making you feel the moral ambiguity, ennui, and general disdain the life of a cop has in this era (or any era since this is a neo-noir novel). Normally, crime-solving is easy in this time periiod because "Pan-Optics" allow them to be reconstructed from the use of omnipresent surveilance from all nearby electronic devices--which isn't so much science fiction as PRISM.
One murder, which involves a refugee who lives among people not so wired, becomes a much harder case to solve which involves a lot of bodies by the end. This is not an action novel but a detective story which is more interested in showing the economically depressed, socially troubled, and corrupt society of 2050 Los Angeles off. It's a character study, relly, as Terri struggles to keep some of her decency in a society that has eroded most of it through simple grind.
An element of the technology which is somewhat unbelievable but quite entertaining is the fact everyone has access to the ability to re-edit movies or television to their liking. Like video game mods, you can have television characters switch their plots in mid-sentence, get naked, or change their dialogue at will. Our heroine loves mutilating the old Nick and Nora movies like The Thin Man.
I love all the little details like the fact skyscrapers have become community housing due to the fact all corporations are based online, the fact social media now coordinates horrible pranks called "Strangers on a Train" as a means of collective punishment, and how people can psychologically scar themselves badly by remixing their worst memories on television.
As a fan of classic noir like Chinatown and modern noir like L.A. Noire, I have to say this was a great novel and fit perfectly into the genre of cyberpunk. Technology has not made humanity better but just given us more ways to screw around with one another as well as scratch the itch of boredom. It gets abused by the government as well as the public equally. It reminded me a bit of Strange Days, really, and that's not a bad thing.