This is the third in the series in which Doranna Durgin created the character of Jess, a horse who was magically transformed into a woman. The three books stand on their own, but can also be read as a trilogy, which is
Dun Lady's Jess
At the start of "Changespell Legacy," Jess has adapted to being sometimes a horse and sometimes a woman. Some of her friends from Ohio who we met in the earlier books are learning magic in Jess's home world, Camolen.
Then the council of wizards who run Camolen are attacked: most of them are killed and Arlen, the powerful wizard who is Lady's friend and her lover Carey's former employer, disappears.
Suddenly Camolen's magic based society collapses, and for the third time Jess is called on to save the world.
This book is more complex and darker than the first two - the relationship between Jess and Carey, who was previously her rider but is now her lover, comes under strain. Not surprisingly, he has difficulty reconciling his love for her as a woman with the fact that he knew her as a horse.
Doranna Durgin knows more than a little about horses, and it shows. Like the first two books in the series, this is a charming and very enjoyable read. I would particularly recommend it to anyone who loves both fantasy and horses.