Winnie Willis, a twelve-year-old girl with a gift for handling horses, finds an old mare in the pasture behind her house and struggles to keep the animal alive, reassure her father, and protect her heart from getting hurt if the horse should die or its owner appear.

After Ranger's apprentice Will battles Temujai warriors to rescue Evanlyn, Will's kingdom of Skandia joins forces with rival kingdom Araluen to defeat a common enemy.