This book leads the reader on a wild adventure when Quentaris, a replica of a city from the early 1300s, is lifted from its bedrock by the Spell of Undoing. A saboteur gets the spell wrong and instead of unravelling the city's prosperity, it lifts the entire city. throws it into a vortex, and hurls it through the rift maze and into another world. The citizens of Quentaris must transform the city into a galleon with propellers, sails and rudders. Unfortunately, the spell also uproots Tolrush, an opposing city which becomes a marauder pirate ship, chasing Quentaris from world to world. The feisty young heroine, Tab Vidler, overcomes many obstacles to help her city.