Well, the first thing that must be said about the trilogy, part 4, that this is, would be that it is really obvious why 40% of the American population is classified as obese - the closest we get to anything healthy being eaten in the entirety of this book is almost at the end (a vegetable sandwich of some sort, though it hasn't actually been consumed by the time "The End" comes around).
That said, this fourth part of Cassie Black's adventures doesn't live up to the previous three: it's not as funny (though there are one or two lol moments), she's not as good a character and her ability to be perceptive seems wholly absent. Some of the other characters (Runa and Fiona, for instance) remain interesting, while others are baffling in the least (Alastair, the supposed boyfriend, who would have been for the chop in any normal relationship - hopefully he will come a-cropper soon, perhaps at the claws of the cat, Pablo?). The bumbling along is fine, to a point, but the story just feels lacking somehow - as the author admits in her afterword, she intended to write a trilogy and that was that.
There is enough in the main plot for one to want to keep going, but this reader hopes more inspiration will come in the remainder of this second Cassie Black trilogy - the first trilogy was really enjoyable, fun and funny, had a great storyline running through it and kept your attention, and wasn't just so focused on eating sweets, 'candies' and pastries.