 Described are the adventures of the title character, Wren, a female human orphan whose best friend Tess is revealed to be the princess of a neighbouring country.When Tess is kidnapped, Wren races to her rescue, making friends with students from a Magic School and learning about her own talents along the way.As part of her adventure, Wren is transformed bodily into a dog, and must decide whether to abandon her quest or try to turn her new shape to the advantage, at great risk of losing her human identity in the process.