While visiting the village bookshop, Simon Kirby-Jones, American vampire resident of Snupperton Mumsley, Bedfordshire, encounters the formidable Lady Hermione Kinsale. Well known as a historian, Simon is immediately pressed into service as a speaker at one of Lady Hermione's famous writers' workshops at Kinsale House, the estate she inherited from her father, the Earl of Mumsley.

Taking tea with Lady Hermione and her assistant, Simon discovers that one of his fellow speakers will be mystery writer Dorinda Darlington. Simon finds this surprising since he is Dorinda Darlington. Under different pseudonyms, he writes both mysteries and historical romances, but both of these identities are secrets, known only to Simon, his agents and editors. Simon therefore wonders who has impersonated one of his alter egos and why.

As attendees and speakers for the conference gather at Kinsale House, Simon perceives that tensions between Lady Hermione's guests abound. Soon these tensions erupt in murder; and Simon finds himself a suspect...since the first murder victim is the woman who has been claiming to be Dorinda Darlington.