Two trains briefly draw alongside each other as they race past a country house and - to her horror - Miss Marple's friend Mrs. McGillicuddy witnesses a man in a passing train car strangling a mystery woman.
Dolly Bantry enlists Miss Marple's help after she and her husband find the body of a mystery woman in their library. News spreads of the disappearance of a glamorous exhibition dancer.
When the vicar in Miss Marple's village declares in exasperation that anyone who murdered Colonel Prothero would be doing the world a favor, he does not realize that his words will come back to haunt him.
A local advertisement announcing the date and location of a forthcoming murder sets a small village abuzz with anxious speculation. Everyone assumes it's a hoax.