A hurricane blows a mundane family straight out of their world and into Xanth, arriving in the middle of a private wager between two demons over whether a single Xanthian can be made to weep. Assigned to settle the bet, one demon takes on a wandering, barely-speaking form and finds an unlikely ally in a woman he's able to make happier than he expected. The twentieth Xanth novel crosses a storm-tossed rescue with a game the demons are playing with mortal feelings.
Summary by Loreful, from public sources