Harley heard the familiar voice and immediately turned around.
She and Hermione had just reached the entrance to the underground classroom, and Professor Snape was standing outside.
Professor Snape forced a smile, but Harley could still tell that something had been worrying him earlier.
"Something's happened at school," Professor Snape said quickly. "We're investigating everyone who didn't attend the Halloween Feast.
"I heard from some students that you and Miss Granger came to Nick's five-hundredth Deathday Party, so I came to find you."
Harley frowned slightly. She hadn't finished asking her questions yet!
Although the Old Man had slipped away after giving her a cryptic answer, there were still plenty of seemingly ancient ghosts around. Surely she could dig up more information from them.
But the school had never required students to attend its various feasts. If Professor Snape had come to find her and wanted her questioned, something major must have happened.
Harley asked, "Professor, what happened?"
"Caretaker Filch's cat was petrified," Professor Snape said quietly, without hesitation. "And the Chamber of Secrets may have been opened."
As she walked upstairs with Professor Snape, Harley learned how serious the situation was.
According to school legend, Salazar Slytherin had fallen out with the other three Founders over whether Muggle students should be admitted.
After a fierce argument with Gryffindor over the matter, Slytherin had left Hogwarts.
But the legend said that before he left, Slytherin had built a Chamber of Secrets and sealed it.
Only when Slytherin's true heir came to the school could the Chamber be opened, allowing the heir to use the terrifying thing inside to purify the school and eliminate all Muggle-born students.
Now, caretaker Filch's cat had been petrified, its tail hanging from a torch bracket. Beside it, someone had written on the wall:
The