This is gonna be short. Katie is a reasonably talented circus performer who was pressured into marrying a circus strongman. The strongman developed a taste for abusing her, so she ran away. Lionel is a reasonably talented stage actor who does variety acts at a small theater by the sea. Despite his many talents and his Air magery, he can't keep his female stage assistants (they take other jobs, get married, etc.). He and his man-of-all-trades/best buddy Fire mage Jack are just despairing of their loss of the latest assistant when Katie shows up.
Surprise! Katie is a Fire mage. Don't worry, that isn't a spoiler. It's even in the cover blurb.
Double surprise (not) is that Katie's abusive husband finds her just as she is figuring out who and what she is, falling in love, etc. Really, if you don't know the formula by now, you haven't been reading any Lackey books.
The major difference in this novel from the previous ones is that the Elemental magic is just grafted into the story as convenient color. The magic does not make any concrete difference to the major plot elements, including the big showdown with the bad guys. The story could have been set, plotted, and resolved without any magic whatsoever, and no major plot points would have changed.
This wasn't the worst of the series, but it certainly wasn't the best. I rate it as a cross between brain candy and my version of a beach bag romance. I'll rank it in the middle of the stack. It certainly wasn't as bad as Reserved for the Cat or Unnatural Issue, but also not as good as The Serpent's Shadow or The Fire Rose.
I picked it up because I tend to like these books.
I recommend it to the people who tend to like these books as well. Really, if you enjoyed more than three of the series so far, your standards are low enough that this should be a good fit.
Books for 2013