After their father is murdered under mysterious circumstances, the three Locke siblings and their mother move into their ancestral home, Keyhouse, which they discover is full of magical keys that may be connected to their father's death.

Twins Tal and Janelle relocate from Ohio to Atlanta, where at their new school High Water is always a beat.

Set against the backdrop of Trinidad and Tobago's mystical Carnival, a gifted and struggling young man becomes the object of intrigue for an older, well-meaning businessman until their worlds collide.