It's a race against time as she struggles to find the kidnappers and their victims. We get an nice glimpse into the imagination of McGuire when Toby visits the Sea kingdom and gets to know the rulers and some of the denizens of the deep, with octopus-form fae and cetacean types, as well. Toby, having once been imprisoned in the form of a fish in a pond for over a decade, has to overcome her fear of the water in addition to exercising diplomacy between the potentially warring kingdoms while she is there.
However, her ...ahem...direct manner somehow charms the sea dwellers, with a dose of honesty and personal integrity that seems uncommon in the world of fae. In the final battle to save the children, Toby suffers an intense and moving personal loss which changes her, and the story arc, forever.
I love the passage where Toby uses a cell phone that's been manufactured to work in faerie:
"Getting through the mortal phone system and into the limited fae exchange requires a unique approach to dialing. I hit al the keys in a clockwise spiral, then repeated the pattern in the opposite direction. I hit the 'five' three more times for good measure."
In some ways the plot of this novel is almost like classic French Farce - you know, where a group of people keep going in and out of doors on a corridor,trying to find each other? - in that Toby continues to try to be a lone wolf, and the "universe" keeps conspiring to make her dependent on and responsible for other people in her world. Having had nothing to do with her daughter, Gilly, since Toby spent fourteen years as a fish in a koi pond, she has managed to lock away most of her feelings about Gilly. When the girl is kidnapped by the same people who took the princes of Saltmist, Toby has to confront those feelings and face the prospect of losing her daughter all over again, one way or another. Duke Sylvester, who obviously regards Toby as the daughter he should have had, rather than the one he ended up with, the venomous and lunatic Rayseline, isn't about to let her skate on her responsibilities, and forces her to see herself as a mentor figure, assigning her Quentin as a squire. Toby figures out that she's going to have to delegate responsibility for the running of her new lands,Goldengreen, so she assigns Marcia as her seneschal. When that realm is threatened, she has to allow Tybalt the King of Cats' people to help her defend it, and all of its refugee population. Toby does, in the end, find a way to absolve herself of responsibility for the realm she really doesn't want, in a rather sneaky yet effective gambit. We get some interesting revelations here about Toby's fetch, May, and some deeper ones about the Luidaeg and her relationship to the roan, which may form the basis of the plot in a future October Daye adventure, unless I miss my guess.