Cal is a Silvertail. She never knew her mother, Sylla, and does not know that with her dying breath Sylla bequeathed her daughter the power of the Merrows - the means to battle an evil that threatens the entire ocean. When Cal meets Jake, a Creeper from the Overbreath, the two are drawn to one another. Cal, like the rest of the merfolk, is astounded when Jake is able to join them beneath the waves. Could he be the one that legend speaks of? The Tide Turner who will save their world? Time is not on their side as Cal and Jake seek the truth about themselves and their destiny...