The Mitford Secret is the sixth and possibly final novel in a truly wonderful historical crime series. Each of the books has followed a different Mitford sister, with Fellowes combining the (fascinating) real-lives of the sextet – from acerbic novelist Nancy to fascist Diana and Communist Decca – with murder mysteries, often with their roots in real cases. Cleverly, she has hinged the series around maid-turned-private detective Louisa Cannon and her now former policeman husband Guy Sullivan, with their relationship providing a sweet and grounded anchor to the high-society world into which they are plunged.
This latest novel sees a psychic crashing the party of Deborah Cavendish (née Mitford, later Devonshire), who is endeavouring to bring together her fractured family during a war that has splintered them over their political disagreements. The bloodied cap of a former servant is found, a young woman who went missing there years earlier, and a cold case mystery blooms in gripping style. Juggling a gripping cast of the rich and famous with the below stairs staff past and present, Fellowes ends the series on a high, with plenty of twists and moments of genuine emotion proving what a superb novelist she has become.