The Girl with Gills

In "The Girl with Gills" by Becca Rogers, thirteen-year-old Effra navigates a hidden world of gilled outcasts called Larkers, who live secretly along the river and conceal their identities from the surface dwellers. After a villainous Larker named Rivermun threatens her brother, Fleet, Effra embarks on a perilous quest to confront powerful forces, including Mother River and a fearsome river serpent, in order to protect her loved ones and their way of life. With the help of a sentient sewer rat and a landlubber girl named Bow, Effra's journey is filled with adventure and discovery in a magical aquatic realm.