Moving between Essex and London, myth and modernity, Cora Seaborne's spirited search for the Essex Serpent encourages all around her to test their allegiance to faith or reason in an age of rapid scientific advancement. At the same time, the novel explores the boundaries of love and friendship and the allegiances that we have to one another. The depth of feeling that the inhabitants of Aldwinter share are matched by their city counterparts as they strive to find the courage to express and understand their deepest desires, and strongest fears.