Sixteen-year-old McKenna Donaldson is the Fire Keeper; she holds the Firestone, the power source for all Fire Wielders in the world. McKenna attends Lalande Academy, a boarding school for people with Elemental powers. Her life is finally starting to become normal once more following the disappearance of her mother and eleven sisters two years ago.
Then her world is once more turned upside down when the Water and Air Keeperstwo girls who have been missingturn up at the boarding school. Emma Richards, the Water Keeper, tells McKenna and her friends that they could find and rescue the important Elementals who vanished two years beforeincluding McKennas family. The group of teens begin preparing for the mission of a lifetime. But Acerbity, an organization that wants Elementals dead, is intent on disrupting their plans, and McKenna soon realizes she can no longer live in fear of her powers. In order to get back what was lost, shell have to overcome what is holding her backeven if it means a personal sacrifice she could never have imagined.