His conversations were hideously detailed and humourless".[1] He was responsible, apparently through spite, for preventing Powell's promotion to the rank of major. When the historian Desmond Seward proposed Capel-Dunn as the original Widmerpool, Powell replied that he "might be on to something".[2] Denis Capel-Dunn married overseas (Cuba) Elizabeth Hessey (daughter of Brigadier William Francis Hessey) and their first daughter Hester Capel-Dunn married the brother of actor Laurence Olivier - Gerard Dacres Olivier; the caricature may well be a red herring.