It's seldom that I start raving over a book before finishing it. Because we all know what happens--it starts off great, we can't put it down, and then the end is... blah. 
 Lucky for me, this one kept my interest and I don't have to take back my premature gushing. 
 We're set in an 1800's alt-reality in Seattle, where the city is sealed off due to a mystery gas (the Blight) that causes illness and, in some cases, zombification. (Let's pretend that's a word.) Briar and her son, Zeke, get a lot of crap because of it. It was Briar's husband, Leviticus Blue, who was the cause of it all. They live outside the wall, scraping by best they can. 
 Zeke is determined to clear his father's name, and--as we sort of expected--scales the wall and heads into the Blight-infested city. When Briar finds out, she freaks out and goes after him. 
 Seattle is a crazy place. You have to imagine that this city has been sealed off for, I don't know, fifteen years, and everyone imagined it was deserted except for the "rotters"--the ones that became zombies due to Blight exposure. But there's a whole underground civilization, a whole world unto themselves. They spend little time on the surface due to the rotters, but keep themselves armed and prepared for the worst. 
 There are some fun characters. An Indian princess; a woman with a mechanical arm; and the mysterious Dr. Minnericht, who may or may not be Blue himself. 
 It's a whole lot of action and a whole lot of fun. I could easily see this being a movie, if for nothing but aesthetics. It's grungy and steampunky with all sorts of great details, and even of the story was completely terrible I would still read it for the setting. 
 I need the rest of this series.