So, here’s the basic mystery of the book:
the POV keeps changing.
No, wait, sorry: that’ the biggest mystery to me. The biggest mystery is the true identity of the protagonist, Agatha Clay.
Here’s the problem: The novel is called “Agatha H and the Airship City.”
And the novel is full of stories about this famous family whose surname starts with an H and whose abilities match Agatha’s.
Gee, I wonder what her identity is.
But aside from that snafu, the novel’s wonderful fun. A well-realized steampunk world, some fun characters, and a scene in which people argue about whether a girl’s “the sensitive daughter of the evil man” or “the easily tricked and quickly killed minion”: what more can you ask?