In 1892, William Richard accepts Headmaster Blake's invitation to teach Defense Against the Dark Arts at Hogwarts Castle in the Scottish Highlands. An unexpected temporal anomaly throws him forward a century to London, where he resurfaces as a fifth-year transfer student at Hogwarts. His mysterious arrival bewilders the entire magical community: Dumbledore recognizes his scholarly excellence despite cryptic murmurs about William's past; the Sorting Hat struggles with his classification; Tom Riddle fiercely defends him; and Harry Potter cannot reconcile accounts of William casually wielding Unforgivable Curses and constructing a tower of troll and goblin heads with his steadfast conviction that William is fundamentally good.