The Veiled Lady — Agatha Christie

Agatha Christie has written a mystery that turns the world of crime upside down, proving there is no honor among thieves, and once again praising the little grey cells of Hercule Poirot. Here's how she proceeds... A beautiful young lady veiled in Spanish lace entreats the sleuth to retrieve a letter she wrote when she was sixteen to a lover. Lady Millicent Castle Vaughan is to be married to the Duke of Southshire, the announcement was in all the papers, but the contents of the letter would surely threaten the Duke's reputation and their pending marriage.