Dylan's Dog Squad--twelve-year-old Casey, his American Cocker Spaniel pup Dylan, and their best friend Sumo--have taken a vacation from search and rescue and are having fun times on the beautiful island of O'ahu. When their new friend Kekoa Ailana comes to Dylan's Dog Squad for help because the precious healing waters of Sacred Falls are being stolen, Casey, Dylan, and Sumo stop chasing waves and start chasing a mysterious criminal ghost.