Horry has been off balance since his sister Ancella married and left Tanqueray Manor with her dog, Glory. Her new husband is kind and charming, but Ancella's first sweetheart, Pom, felt like part of the family, and Horry misses him. His brother Guy is changing fast, Horry is falling behind, and there's something amiss with the twins.

A letter requesting the return of something the Tanquerays don't have brings a small mystery. Horry delivers the answer, and in the process he meets the galleonfee maid Vigdis. They enjoy a perfect day, but back at the manor, Horry's world keeps shifting as he learns astonishing facts about his family and especially about his beloved pony, Lis.