Princess Aria, the mermaid princess, is forced to marry Derek, the Siren King, to preserve peace for her people. Believing Aria murdered his parents, Derek robs her of her voice and subjects her to daily punishment and humiliation. When she finally uncovers the truth behind the old tragedy, she is willing to sever her tail to break their blood bond (dissolve their marriage). Yet she discovers that Derek, her once cold husband, will never let her go.