Pomona carried a large bundle of mint down to the Slytherin dungeon.
The students were all on holiday, so she had to deliver the ingredients herself. Midsummer sunlight filtered through the lake and shone in through windows that could never be opened, turning green—entirely different from the scorching sunlight she had endured while picking mint in the herb garden.
Though cool, it was far too dark; even in broad daylight, the magical lanterns had to be lit.
"Severus!" she shouted, her voice echoing through the great Potions classroom.
"If you go out now, it'll be a bad idea," Pomona continued. "Don't think that just because the trial is over, everything is over!"
There was still no answer, so she set down the herbs and went to wash her hands at the gargoyle-shaped faucet in the corner of the classroom. Then, from the corner of her eye, she spotted a glowing object circling around her.
She turned and found that it was a firefly. After flying around the classroom for a while, perhaps it had grown tired, so it landed on a desk and continued flashing.
"How did you get in here?" Pomona asked the firefly. Naturally, it did not answer.
But she quickly discovered that there was more than one firefly in the classroom. Following their flight path, she went around the glass jars lined up against the wall and reached a small room at the back of the Potions classroom. A cabinet had been moved aside, revealing a bottomless hole. The fireflies were emerging from it.
"I knew it," she muttered, raising her wand and casting Lumos before stepping inside.
Even if Snape did not enjoy exploring as much as the Marauders, his curiosity was still intense. Many people had searched for Salazar Slytherin's Chamber of Secrets.
Before long,