London, late XIX century. Cora Seaborn, whom the husband treated with as indifference as he could, is relieved after his death. But so far she does not dare to new relationships. The woman leaves the capital and settles in a remote corner of Essex. From the terrified locals she hears a strange, mystical story about a snake, after the appearance of which people began to disappear in the village. However, Cora does not believe in this and together with the local pastor tries to calm everyone down. And between these two, seemingly completely different people, there are relationships that change their lives. In this way, all the characters are drawn into a mystical and mysterious story in which pain, fears, science, religion, politics, life, death and love are intertwined in its various manifestations