This is my favorite of the series so far. Most of the pacing issues I had with previous books, the sort of situation where everything goes to hell in such a rushed fashion the reader is almost left behind, are delightfully absent in this one. The Commodore drove me nuts, as usual, with his eternal put-upon misery, but even that had a fantastic pay off by the end. I think, after finishing the book, that Commodore Black was one of my favorite characters. His scene at the end is just so visceral. Not punches pulled. And I loved it.
Add in Jethro Daunt, the Circlist priest who was kicked out due do the fact he hears old gods (possessing an amazing talent for deductive reasoning), and his companion Boxiron, the head of a Steamman Knight inexpertly attached to the inferior man-made machine body (with an issue with aggression and stuck gears, not to mention a black market skill set) , and Fire Sea has a cast that not only grabs the readers attention but pulls them through each and every page. Every now and then Jethro appears to be a fantastic hat tilt to Sherlock Holmes, and on occasion made me chuckle with appreciation. His first scene in the book really drives that impression, and I was unable to get it out of my head whenever he was in a scene for the rest of the book.
The main protagonist is Hannah Conquest, ward of the church and math prodigy. She is interesting, but serves more as a reason to bring the rest of the cast together than anything else. Purity and Molly remain far more compelling heroines in my opinion.
The isle of Jago itself presents a creepy, hellish setting. From the corrupting domain of the valvemen to the beasts that roam the exterior of the city there is an omnipresent sense of danger and horror. The book itself is full of murder, conspiracy, and skulking Old Gods, which combined with the setting adds the twisted horror aspect I have come to love and expect from Hunt's books.
The Ursine race added another interesting culture to the social menagerie that populates the world, and the fact the plot hinged on something more mundane than most of the other novels- race/culture conflict between the Humans and the Ursines- the book as a whole was a more intriguing read.
This is a wholly brilliant addition to the series. I highly recommend picking it up!