She couldn't remember what gave her the idea. Maybe it was sitting idly in the Transformation class, just watching the woman. Her precise movements, her stern manner, her soft Scottish accent, her strong will.. and the long green velvet dress. The hair, forced to  obey her iron will, tied back into a bun without a single strand escaping.


"I'll be she was a right terror, back in the day," she thought. And that's what decided her.


Her costume was a mass of spells, spells to color her hair, spells to turn her school robes that shimmery crow's feather green/black. The crumpled witch's hat, (three spells to get that right) the plaid shawl over her shoulders (just an ordinary scarf in real life) the buckled shoes, and the sprinkling of ginger cat's für around her clothes. She'd had to borrow a friend's spare glasses to spell into shape: square half-lenses to look over, wire rims ,earpieces wrapped around her ears. She wondered if McGonagall would be amused or outraged.


Well, she'd find out at midnight. For now...into the sound of eastern music and the smell of exotic spices she went, pausing only to give her best sniff of disapproval.