It's the story of Nick and Todd, a couple of guys from Brooklyn who form a friendship as kids and continue it into adulthood, where it's really put to the test. I can't tell you exactly how without spoiling things, but I can tell you that it involves plenty of violence, low-life characters, cops, killers, conspiracies, gangsters, double crosses, and surprises. There's even some romance and happiness, though of course the latter doesn't ever last very long.
Bruen tells the first half of the tale, which is Nick's, and Coleman finishes things off by telling Todd's story, which is sort of the same story, except that it's not. We see some of the events from each perspective, but of course some of them we see from one perspective only. If that sounds tricky, it was probably tricky to write but Bruen and Coleman make it easy to follow.
Besides the novel, there's some bonus material: an essay by Coleman that explains how the book was written, and three interviews conducted by Craig McDonald, one with Bruen, one with Coleman, and one with Allan Guthrie, who edited the book.
This book has everything going for it, and I think it's going to be a big seller. Grab it in September and see if you agree.
Update: David mentions in his comment below that the bonus material is available only in the galley but that it'll be available on-line for free.