Neville looked nervously at the teachers, half their faces seemed surprised the other half seemed very skeptical. "We started by looking at Slytherin himself; and the fact he was a parselmouth. So we made a list of creatures that ability would allow him to control, then we quickly eliminated anything non-magical. Which left us with nagas, lamias, and basilisks. We found out that lamias eat children's souls and we don't think Slytherin would bring one to a school regardless of how he felt about the other founders. Nagas' abilities didn't match. Which left us with basilisks, whose gaze turns living things to stone. We think that the creature is a basilisk, and that the reason no one has died is because they didn't meet its gaze directly.
"Hermione asked Binns about the Chamber. He wasn't very helpful, but he did indicate that it was thought the chamber opened fifty years ago. So we did a search through the records. We believe," he gulped, "that the previous headmaster made a mistake. If we're right and the creature is a basilisk, then Hagrid was wrongfully expelled because the creature he had brought into the castle was an arcomantula not a basilisk. He was not responsible for Myrtle's death. Rather we believe it was Tom Marvolo Riddle and that he lied to Headmaster Dippet and framed Hagrid."
"We believe the entrance is somewhere in Moaning Myrtle's bathroom based on what she told us girls about what happened when she died." Hermione spoke.
Professor Snape said, " Very well that explains the what and gives us a probable where, you say that you think this Riddle person was behind it fifty years ago? Parseltongue is an inherited ability surely we can trace his family." He found himself very curious about Tom Riddle. The age was right, was it possible that Voldemort was some sort of pseudonym?
"Tom had no offspring." said Headmaster Dumbledore. "You children have obviously put thought and effort into this. But Riddle was the last of his line and parseltongue is such a exceedingly rare ability-"
"Could he have come onto the Hogwarts grounds without you knowing, Headmaster?" Hermione asked.
"No I'm afraid that is quite impossible."
All the students but one developed downcast looks.
"Which leaves what, Headmaster?" asked Harry. Paying close attention to his tone he continued, "Possession? Did the school wards not get reset after last year's fiasco with Quirrell's possession by Voldemort to warn you of such things? You have our findings Professors. Now, how about you set a trap, catch the perpetrator, and bring in the exterminator before more students are hurt, or killed."
As Harry said the name, everyone but Albus jumped. McGongall scowled at Harry's words. If he hadn't said them in a respectful tone she'd have removed points for disrespect.
"Headmaster, I'm sure if you ask, my Aunt Amelia would happily help you." Susan said.
"I'm surprised, you children did a very good thing in doing this research. We, teachers, have been so concerned about trying to keep you all safe that we overlooked the fact that by identifying the problem we could solve it. I think that you've all earned twenty points each for your houses." Professor Flitwick said before either the Headmaster or his deputy said anything.
Professor Snape said, "If, if their research is correct I think we should add an additional thirty points to each student, maybe even awards for special services." He saw the pleased and sly half smile begin to form on Lily's son's face. "And since a basilisk of such a great age is sure to render many valuable parts, perhaps a credit towards their tuition say three percent of the value each?"
Pomona Sprout said, "That does indeed sound fair." She was thrilled that three of her House's students were a part of this group.
Minerva frowned, mostly at the five Slytherin students. But due to the approving nods the rest of the teachers were giving the idea, she said nothing. She had developed an aversion to Harry Potter. Mostly because it was extremely difficult to deal with seeing thinly veiled contempt coming from the face and eyes that reminded her of two of her favorite students. The boy was always on the surface respectful, but those eyes told their own story. She felt guilty and self-conscious whenever they were in the same room together. To have him here, pointing out the short-comings in the way the staff had been handling the problem with the Chamber's monster, it was as if someone had stuck something very hard in a very uncomfortable place. It reminded her all together too much, of the disaster surrounding the philosopher's stone last year.
Although part of her had started off liking Miss Granger, she now felt differently. The girl, while an excellent student, had fallen in with a questionable crowd, and had made no effort to become friends with anyone in her own house. It was unfortunate the girl lacked so much in terms of understanding the social realities of life at Hogwarts and in the wizarding world in general. Minerva was quite uncertain of what the hat had been doing sticking the girl in the house of the lions when she would have been better off in Ravenclaw.
Neville Longbottom had been a thorn in her side since day one. From his first term he was like a small splinter. He had originally seemed hopeless and he hadn't made any friends with his year mates in the Gryffindor dorm, if anything he'd made enemies. He'd squared off and made it abundantly clear that he was friends with Harry Potter, the bane of Minerva's existence, and she could like it or lump it. The sad part was, that the way things were going scholastically with the boys of that year group odds were when it came time to choose prefects Neville would be the top candidate.
Albus Dumbledore also felt very uncomfortable. He hadn't put much thought into solving the problem of what was happening to the students. Protecting them, yes, getting to the bottom of how Tom was able to do such a thing, not really. He had been a little busy trying to consolidate his power after the summer's courtroom disaster and the ensuing fallout.