"Addiction and mad science come together beneath the poisonous Dark Cloud of Southwatch"
The city of Southwatch is plagued by a poisonous cloud that cuts the city in two, vertically. Beneath the Cloud, Mellia fixes the gas masks and filters that are necessary to survive the foul air.
There should be an interview coming up sometime on the Darkside Codex blog, as well as other little tidbits about the story and about working in a shared world in future posts here.
Note that this is not a Spire City story at all. It's secondary world, fantasy steampunk, which does tie them together in a way, but it stands completely alone separate from that. And quite separate from the other Darkside Codex stories that will continue to be released, though hopefully there's some good synergy there among them all.
In addition to the publisher, you can purchase this ebook from Barnes & Noble, Amazon, and Smashwords (and likely others to be added later).