Jonah Hancock, a portly widower of 45, is about to have his life upended by two mythical creatures.
The first is celebrated courtesan Angelica Neal, a capricious yellow-haired enchantress. The second is a mermaid.
Jonah has been anxiously awaiting news of a missing ship when he learns its captain has exchanged it for a mermaid.
And not a mermaid of shining hair and sequinned scales but a creepy, desiccated little corpse, “more of a sea-goblin” with fangs and a tail, fearful claws and a snarl for a face.
However, Hancock is persuaded he can recoup his losses if he puts the creature on display.
So he becomes embroiled in the ambitions of Mrs Chappell, who runs a high-class brothel and plans evenings of entertainment with the mermaid exhibited as the star attraction.
Angelica is charged with keeping Mr Hancock happy but the staid widower, haunted by the memory of his dead wife and the ghost of his small child, is appalled by what he sees in the brothel and dismayed by the power exerted by his mermaid.
He sells the curiosity for an unimaginable sum – but he cannot dispel the siren call of Angelica Neal.
Her demands lead Hancock and his household into a dangerously melancholy place where desires, expectations and unfulfilled longings exert their power in the most unexpected ways, allowing loneliness and doubt to beset their affectionate hearts.
The result is a wonderfully written and richly descriptive novel, its brilliantly drawn characters driven by heady and dangerous desires.