Britain Has Four Kinds of Weather

On Tuesday evening, Professor McGonagall summoned Gavin to her office alone.

A light rain fell outside the window.

Fine strands of rain slanted against the glass, as thin as cow hair, weaving a net that seemed to have no end.

Nights at Hogwarts were often like this: damp, cold, quiet, and gloomy, as though the castle itself expected nothing from the weather.

When he entered, Professor McGonagall sat behind her desk marking assignments, with a stack of parchment rolls at least three feet high in front of her.

Her glasses rested on the bridge of her nose, and her quill moved swiftly across the page, leaving a string of bright red comments—

Gavin glanced at one. It said, more or less, "Please do not call a failure an 'intermediate form.'"

"Sit down, Mr. Gu."

Without looking up, Professor McGonagall pointed her quill at the chair opposite her.

Gavin sat and waited about two minutes. Professor McGonagall finished marking the assignment in her hand, set her quill in the inkwell, removed her glasses, and folded her hands on the desk.

"Professor Dumbledore told me you already know about Animagi."

"He mentioned them."

"Did he tell you how to become one?"

"No. He only asked whether I knew about them."

Professor McGonagall nodded, her expression as stern and businesslike as ever, then rose and walked to the blackboard.

There was a small blackboard in her office, with last week's Transfiguration Club lesson points written on it in chalk.

She tapped it with her wand. The writing erased itself, and new words appeared: a flowchart divided into four steps, each marked with a time.

"Becoming an Animagus is one of the crowning achievements of Transfiguration."

"The difficulty isn't really the transformation. It's the complicated process."

"Step one." Professor McGonagall pointed her wand at