Mermaid heir Cassius seduces mutant prisoner Elvin, secretly exploiting his rare power to cleanse Loran’s deadly poison. Betrayed and cast into the abyss, Elvin disappears without a trace. Three years later, he returns as the ruthless Lord of the Abyss, powerful enough to make those who destroyed him pay. Now Cassius must sacrifice everything to earn redemption from the man he once betrayed, even if the price is his heart and soul.