Murder in Reproach — Anne Cleeland

This seemed like a cut-and-dried case of suicide to Detective Sergeant Kathleen Doyle; the decedent -- a wealthy theatre patron -- must have decided that life without her famous husband was too hard to bear, and so she'd ended it.

Indeed, nothing about the tranquil scene would indicate foul play, save for the housekeeper's insistence that something was amiss. The girl was certain that her mistress would never take her own life, and equally certain that she would never hold a peacock feather while doing so. After all, everyone in the theatre trade knew that peacock feathers were bad luck. . .