After leaving the Magic Research Institute, Murphy Apparated to the area near Hogwarts Castle.
Then he turned into a stream of black smoke and flew into the castle, landing at the entrance to the Great Hall.
The caretaker, Argus Filch, was mopping the floor. Murphy's manner of arrival startled him, but once he saw who it was, a fawning smile immediately spread across his face. "Mr. Darkholme, hello."
Murphy nodded lightly, pushed open the doors to the Great Hall, and walked in. He saw Professor Flitwick waving his wand, arranging the tables, chairs, and benches neatly, and setting up thousands of candles beneath the Great Hall's vaulted ceiling.
"Professor, long time no see."
"Oh! Murphy!" Professor Flitwick was startled, then smiled. "It seems the title of youngest professor at the school is about to change hands."
"It's my honor to work with you, Professor."
Murphy was happy too. Professor Flitwick had been his head of house, and also Murphy's favorite professor back then. Compared with the stern Professor McGonagall, or Snape, who had never exactly looked kindly on him, Professor Flitwick had suited Murphy's tastes better in both teaching ability and teaching style.
Professor Flitwick hopped down from the dais, raised a hand, and patted Murphy's arm. "I heard you're joining the school as a governor as well. Remarkable, truly remarkable."
The two chatted for a while. Filch went to inform McGonagall of Murphy's arrival, and she hurried over as well, arranging an office for Murphy on the seventh floor and asking for his opinion on his class schedule.
"If you want to teach two houses together, we can put one class on Wednesday and one on Friday..."
"Can I teach all four houses together?" Murphy asked.
Aside from his goal involving the Philosopher's Stone, Murphy had come to Hogwarts