"Go back to the common room immediately!"        Newton whirled, his heart in this throat. But it wasn't Filch, or even that rat-fink Gryffindor Head Boy. It was only his house ghost.        "Blimey, Baron, you gave me a start!" the boy whispered, hoping the apparition would follow his example and lower his voice. Their presence must not be detected by those on the other side of this door at the top of the moving spiral staircase.        "You've got no business spying on the headmaster!" the Baron insisted. "Go back to the common room. Now!"        The brown-haired fourth-year folded his arms across his chest and the Baron marveled at his cheek. Newton was his favorite among the current crop of Slytherins, but the youngster's sweetness of face was deceptive and his bespectacled hazel eyes suggested a tenderness he seldom bothered to employ. "Or you'll tell whom, exactly?" he demanded of the specter floating before him.        The Baron looked away. His eyes fell on the closed door to the headmaster's office and his morose face grew even more somber than usual. He had no patience with Slytherins who eavesdropped. Nothing good ever came of it. But Newton just nodded.        "We know he's gone, Baron," he accused softly. "I don't suppose you'd care to tell us why?"        Owls and rumors had been flying all day, starting in the wee hours of the morning a short time after the Halloween festivities had ended. The feast had lasted longer than usual, Halloween being on a Saturday this year. The last of the Slytherins had exited the Great Hall around midnight, completely unaware it would be the last time they would see their portly head of house.        They'd sought him out Sunday morning in response to the first strange messages that had arrived from family and friends. The missives were brief, almost cryptic, as if trying to caution without revealing anything incriminating.               "Something's gone wrong. Watch out for yourself." "Don't fuss. We're not fussed. Better this way, really." "Keep your eyes open and your mouth shut."        They'd found his office deserted and his quarters a shambles.        "Someone left in a hurry."        That was Jane, Newton's fellow fourth year and pony-tailed best friend, who'd pushed aside the pitch-black bangs that were forever falling in her eyes as she'd turned morosely to the house's self-appointed leader, a blonde seventh year named Mark Coleman. Back in the house, the Slytherins were panicking. Several were packing their bags, preparing to flee. But Coleman had merely shrugged and sauntered off, and Newton expected no better from his female counterpart, a redhead named Mel. 17-year-old Mel liked to present herself as being devoted to her housemates. But it seemed to Newton that, in the end, Mel made everything... from potions to Slytherin House to magic itself... about Mel.        The fourth years had decided to take matters into their own hands.        "I'm not going back without some answers, Baron," Newton insisted now, leaning confidently against the doorframe. He was sure the house ghost would have no choice but to fold in response to such righteousness. But the Baron trumped his ace.        "The other ghosts may report back to Professor Dumbledore at any moment. I won't be able to protect you."        So Newton returned to his house to seek out Jane and see if, together, they might be able to stop some of the panicky Slytherins from fleeing. Maybe later, the boy speculated as he traversed the castle corridors, we can persuade the Baron to slip into the headmaster's office and have a talk with the portraits.        He was dying to know what was going on behind that closed door. Suddenly Severus