ISABELLE LOFFLIN can't stop worrying about her sister. With the camp in chaos and the prophecy close to an end, Brett's safety is top priority. However, when Isabelle demands another dispatch the trip may come at a price she's unwilling to pay. The final battle approaches and the fate of the Descendants rests heavily. After learning the truth about her mother and Calix's mysterious past, Isabelle is determined to fulfill her destiny. With her balance of light put to a test, she discovers this is a fight she can't handle alone. Calix, Onyx, Ash, Jeremy, and Brody step up against Caradoc's followers, but will their help be enough to defeat the darkness?