In the novel Postern of Fate, Mrs Winifred Griffin (née Morrison) is an elderly neighbour of Tommy and Tuppence whom Tuppence approached for background information on Mary Jordan and Alexander Parkinson. Tuppence thought she was the oldest inhabitant in Hollowquay (94, according to village talk) but at the same time, still has a good memory. Mrs Griffin was evidently a great character in the neighbourhood. According to what Tuppence had gathered, she was reputed to rule everyone with a rod of iron: "She bullied the vicar and she bullied the doctor and I think she bullied the district nurse and all the rest of it."
Mrs Griffin proved quite informative. She turned out to be the godmother of Alexander Parkinson. She remembered Mary Jordan as someone who was "mixed up" with an affair relating to naval submarine secrets, and some talk that Mary Jordan was not her real name. Mrs Griffin also linked Tuppence up with Mrs Henderson and Mrs Hendley who she believed could tell her something useful. Later Mrs Griffin sent Tuppence an old photo album which contained, among other shots, a snap of Mary Jordan.