Oh, the cleverness and the rich language and the delightful characters. These are what I love in middle grade fiction, and the comparisons to a certain series (Mysterious Benedict Society) are well founded for these exact reasons. The mystery here is lighthearted yet profound in its depth which isn't fully revealed until the close. Hints of what might come in the second book are just enough to keep young readers eager for the next. (And old readers like me, too!)