Umbridge has no idea what is coming. At a tense 6 a.m. staff meeting, Severus quietly sets Dobby on a very Slytherin revenge plan: a harmless–but–humiliating potion slipped into the High Inquisitor’s food. By breakfast, the entire school watches Umbridge suffer a spectacular “accident” at the staff table and flee the Great Hall wrapped in McGonagall’s cloak, while Madam Pomfrey’s remedy only makes things worse.
Down in Defence, the fallout turns into opportunity when Snape walks into Umbridge’s pink classroom and takes over. He clears the desks, introduces the Patronus charm for OWL prep, and shocks everyone when Neville Longbottom produces a full corporeal plant Patronus before most can manage a wisp of mist. Harry’s own Patronus shifts from stag to doe, leaving Snape, Hermione, and Ron rattled for very different reasons.
The chapter closes in the dungeons, where Harry watches over a basilisk egg and Snape quietly explains why Patronuses change, what it means that Harry now shares a doe with Lily and Severus, and why Neville needs his own wand before the war truly starts. It is classic “A New Place To Stay”: Umbridge humiliation, staff politics, and deep, character-first Snape–and–Harry guardianship with canon-rooted magic.
