Unpublished material

• Eugenia and Eugenics (stage play)
• Snow Upon the Desert (romantic novel)
• The Greenshore Folly (detective novella, featuring Hercule Poirot, expanded into the novel Dead Man's Folly)
• Personal Call (supernatural radio play, featuring Inspector Narracott - a recording is in the British National Sound Archive)
• The Woman and the Kenite (horror) An Italian translation is available on the internet La moglie del Kenita
• Butter in a Lordly Dish (horror/detective radio play, adapted from The Woman and the Kenite)
• The Green Gate (supernatural)
• The War Bride (romantic/supernatural)
• The Case of the Dog's Ball (short story, featuring Poirot, expanded to the novel Dumb Witness and related to the short story How Does your Garden Grow?)
• Stronger than Death (supernatural)
• Being So Very Wilful (romantic)
• The Last Seance (stage play)
• Someone at the Window (detective stage play, adapted from the short story The Dead Harlequin)