Don't get me wrong, this book nicely continues the Elizabeth Cage saga. I'm a fan of Jodi Taylor's. I've purchased and read almost everything she writes. I'll continue to be a fan.
So why the 3-star rating?
I'm a voracious reader. Often my purchase decisions are swayed by the length of a book, especially if it's an author I don't yet follow. To my way of thinking, a novel of less than 300 pages has either not had the plot and/or characters fully developed, or the story line is truncated to facilitate the production of an endless series, based predominantly on sales. If you're not yet a Jodi Taylor fan, then you need to know there's a little padding or false advertising in the book description!
It's not a 379-page novel. Try less than 300.
The prologue begins on page 13. The book ends on page 302. The remaining 77 pages (and that's a lot, Jodi...shame on you for letting this happen), are multi-page adverts for her other books.
I read once that before even getting Book One of her Harry Potter series published, the author knew it would flesh out into a 7-book series. And despite pressure from adoring fans and her publisher, she stuck to that. Now her series is iconic. Jodi, channel that in your future series, because I can tell you WILL be writing profusely as long as you draw breath. When a story comes alive and you just know it will be a series, let the PLOT decide the length of that series, nothing else. In the end you'll elevate your writing into a whole new level of proficiency, and that will attract more readers.
Thus, I'm not saying don't buy this book, especially if you've liked the series so far. Just be aware that it's not as long as you hoped, for whatever reason you decide fits.
And Jodi? Next time put a one-page listing of your series and stand-alones at the start of a book, a la Nora Roberts. Not a 77-page embarrassment.