3.5 stars (wishing there was a way to indicate half-stars!)I'm sure I must have read this in grade school or middle school... and while the book still has its appeal, it's interesting to me to see how far we've come from the 70s. As a young girl, this book held mystery, thrills, romance, and a bit of the "woo woo" in the ESP sense.It's still a fun book to read, but to my jaded, much older self, not as much of a mystery, suspense, or thriller. But that's not because there's anything wrong with the story or the characters... it's just a difference in the "sophistication" of and abundance of book, movie, and TV plots since the book was published. And it's great to find a PG-rated story!So much to love -- Byrony, the mystery of where Francis is, the Twins (James & Emory), Rob, the Upplands, and the whole story, really. Despite the thorough and lush description, I must admit that I didn't quite understand or picture the maze or the little garden house... or the whole sluice system to keep the place from flooding. But it doesn't really matter, because once I picked up the book, I didn't want to put it down.