After a season in Regency London, Bianca and Isabella de Hyville are back home in the Gothic house created by their father, who for years has been at daggers drawn with their neighbours, the Thrinbys. Isabella fancies herself in love with Sir Ranulf Thrinby, but knows their relationship would never be allowed to flourish. When Bianca disappears, having befriended a runaway boy who claims to have been maltreated at Thrinby Hall, Isabella must try and find her and protect her from the wrath of both families...