This is the fourth book in the new Black Ocean series detailing the back stories for the wizard Mordecai the Brown (known as Mort to his friends) and Ramsey family. This story, while while wouldn't call it a second part of the previous book, directly follows up on those events, picking up directly where it ended. I highly recommend reading that first.
Expecting that these four books will soon be bundled into a mission pack (like the other Black Ocean series are) makes it a good capstone for the initial set. I didn't feel like I wanted the previous book to continue, but I definitely liked how this built on it, and the consequences of that story (sometimes it is really hard to write about these without giving away spoilers!)
The cinematic feel to the story continues, which is a hallmark of this series. I know I have said it before, but reading these often feels like watching a good show.
I look forward to the next set of books in the series (and I personally am hoping for a bit of a time jump now - I want to see Brad in the academy and learning to be a pilot (and adding meeting more of the characters from the other series)).
Because it is all fun and games . . .