During the first week of term, the whole of Hogwarts Castle ran like a finely crafted, wound-up clock, moving at a frantic yet orderly pace.
Even the air in the corridors seemed thinner than usual, with students and professors hurrying everywhere.
The lights in the Academic Affairs Office stayed on almost all night, and attendance sheets and disciplinary reports awaiting review piled up outside Sirius's office.
Mr. Filch patrolled the corridors with his Mrs. Norris with unprecedented enthusiasm, trying to catch any unfortunate soul who dared break school rules in the very first week of term.
Even the prefects were busy collecting the points professors had awarded and deducted in each class, as recorded by the class representatives, then compiling them for the Academic Affairs Office to review.
For the sixth-year students bold enough to take the brand-new elective, "Advanced Fantastic Beasts Breeding," however, the real challenge had only just begun.
They were gathered at the edge of the Forbidden Forest.
Before them stood a building imposing enough to inspire awe in anyone.
It had once been a greenhouse abandoned to vines and the passage of time.
Now, however, it had undergone a complete transformation.
The original glass had been replaced with crystal so thick they could not see through it, its surface flickering with a faint runic glow that rose and fell like breathing.
The framework supporting the entire dome was made of werewolf-forged steel with a dull metallic sheen, so sturdy it inspired despair.
The heavy door had neither a knocker nor a handle.
There was only a magical seal of dizzying complexity rotating slowly at its center, making it look more like the entrance to the deepest vaults of Gringotts than a classroom.
Just then, Hagrid appeared.
He wore a brand-new dragon hide apron thick enough to