In 1893 Cornwall, a doctor is sent to investigate a miraculous claim that a fisherman's wife has cured tuberculosis, but what he discovers is more than he can believe.

Ali Cook
as Gregory Lutey

Beatie Edney
as Betty Lutey

Simon Armstrong
as Lutey

Clara Paget
as The Mermaid

Roxanne Cook
as Edith

Thomas Stocker
as Arthur