The book concerns Cass, a survivalist who never leaves home without her backpack full of such important things as rope, a compass, and bubblegum, and Max-Ernest, a very logical boy who has trouble telling a good joke. These eleven-year-olds stumble upon the Symphony of Smells, an assortment of scents labeled as musical instruments. If this sounds like synesthesia to you, then you're ahead of the game. A kids' book with synesthesia as a plot point, how cool is that?! The Symphony of Smells belonged to a dead magician, and after they discover his notebook, they're swept up in the quest for the Secret! (No, not that one. The good one, the one that lets you live forever and stuff.) Word games, anagrams, coded messages! It's good times.
The story proper is about what you'd expect. Cass and Max-Ernest, strangers at first, bond and become friends during their adventure, although it's done rather well and doesn't take the easy way out. They learn more about the magician, get themselves in trouble, encounter a plot twist or two, and get themselves into more trouble. You know how these things go.
The real fun, of course, is in the narration. Bosch tells the story to the reader, frequently giving the reader suggestions on how to view a particular scene or helpfully giving more background information or admitting that he made something up. And the book is structured as if he's telling you the story right then, so he will hesitate before advancing to a particularly dire section or refuse to tell you something or tell you to look up a word. The intended audience, though, is obviously a younger crowd, who may be getting their first taste of metafiction, not having read House of Leaves. That isn't to say that an adult can't enjoy it (obviously, since I did), but I would especially recommend it for kids. There are also cute drawings that introduce each chapter.
The snarky narrator is reminiscent of what little I know of Lemony Snicket; I haven't gotten around to reading A Series of Unfortunate Events yet (so many books!), so I can't really compare the styles. But I suppose it's only appropriate that as I neared the end, I got the sneaking suspicion that...yes, I had stumbled into a series. Dammit! I mean, as I neared the end, I actually did hope that there was a sequel because I wanted more adventures with Cass and Max-Ernest, who are great characters, but I didn't realize the book wasn't completely stand-alone when I bought it. The second book is called If You're Reading This, It's Too Late! Oh, Pseudonymous Bosch. You're so adorable! There's a third book on the way, apparently called This Book Is Not Good for You. And now I have to read them to find out what the goddamn Secret is! Oh, YA metafiction, why do I find you so entertaining and amusing? And at six bucks a pop, I can actually collect you in paperback.
Booklist called the book "Equal parts snarky and delightful," which I think is an apt description. It's snarky! It's delightful! Why wouldn't you want to read it?