A story that has left elements stuck like flypaper in my head for many, many years. On re-read, I find it just as compelling--perhaps my only complaint is that the ending is a little under-written, as if the publisher was trying to keep her within a certain page length. Knowing Tepper and the books she has put out since, I wouldn't be at all surprised. Which is too bad, really, because when you read this book, you will be wanting more, more, more.Unusual in the Mavin series, it's largely from the perspective of Beedie Bridger ("Sausage-Girl" to Mavin), and her adventures with Mavin evolving into a rite of passage for Beedie. Mavin has come to the Rift exploring, searching for her long-lost sister Handbright. Beadle is a member of a community living within a giant chasm, and it's another one of the small populations inside the Game-world, a fascinating sub-culture coping with environmental extremes. (Incidentally, whoever writes the back cover synopsis to this series ought to be sent back to sixth grade for book report practice). It's also a clever device that keeps Mavin from problem-solving in strictly shape-shifter ways, as she doesn't want to give away her identity to anyone more than Beedie. It allows a fascinating twist to the narrative as well, as Beedie is clearly the product of a loving family in a somewhat insulated society, and both Mavin and the reader have many moments where they are two or three jumps ahead of innocent Beedie. In order to free Handbright from the politically disastrous situation she is in, Mavin and Beedie undertake a quest to climb to the bottom of the chasm and investigate what has been eating the tree roots that form the physical structure of the rift-dwellers' community. With them come Roges, a member of the provider Maintainer caste, and Mercald, the Birder-priest who has gotten Handbright into the messy situation. The journey gives Mavin a chance to reflect on her problem-solving skills in the past, and the chance to learn more of what Mavin has been doing since The Song of Mavin Manyshaped is welcome.Tepper's favorite themes worm their way in here, including the lecherous male figures and the underhanded power struggle between factions, but I don't feel it was overbearing. Including Mercald as a representative of religion on the journey gives Tepper an opportunity to gently muse on implications of religion and belief. Perhaps a little incongruous but fascinating was when the group encounters the Thinker, clearly Tepper thumbing her nose at philosophers who intellectual problem-solve without experimentation. The multiple threads of the plot are woven well, but the solution to the mystery is almost anti-climactic--until they encounter a complicated and somewhat horrific second mystery. Kudos for the creepiest flypaper ever.