325 The Equestrian Teacher's Problem

When he returned to the living room, Klein picked up a letter opener and opened the envelope before taking out Isengard Stanton's letter.

The famous detective wrote:

"Your idea has greatly helped us. Please allow me to thank you here first.

"After receiving your letter, we immediately organized some people to sweep through crucial areas. As expected, we found some clues, and quite a few stray animals that had frequently appeared and were remembered by the residents had disappeared.

"In the process, we also noticed an interesting thing. Four years ago, in the serial murder case, yes—the targets were single prostitutes with a child. Quite a few people living near the scene of the crime had mentioned that although the most suspicious teenager was eccentric and vicious, he was quite fond of animals, especially a large black dog.

"After the boy died in the gang firefight, the people who lived around him never saw the dog again.