Chapter 6-21 The Unknowable Room
- Harry finds a new incantation in "Advanced Potion-Making" , the Prince scribbled ¤ Sectumsempra in a margin which is supposed to be 'For Enemies'.
- Apparition tests are announced.
- Kreacher and Dobby pop in in the common room. Draco turns out to be breaking no rules, but keen to visit the seventh floor with a variety of other students who keep watch. Harry, Ron and Hermione realize he has been visiting the Room of Requirement. He never managed to see the room on the Marauder's Map. Hermione supposes the room is Unplottable. Harry thinks that the other students on watch could be Crabbe and Goyle having used nicked Polyjuice Potion from their first Potions lesson. They could have been dropping the scales and toad-spawn to tell Draco not to come out.
- Hermione thinks Harry should focus on getting Slughorn's memory instead of trying to figure out how to follow Draco into the Room of Requirement.
- In the Daily Prophet there is news that Mundungus Fletcher was arrested and sent to Azkaban, someone called Octavius Pepper has vanished and a nine-year arrested for trying to kill his grandparents, they think he was under the Imperius Curse.
- Harry tries to get into the Room of Requirement but can't find it.
- In Potions, Snape explains the difference between ghost and Inferi, Seamus asked about Mundungus pretending to be an Inferius when caught. Snape calls Mundungus a smelly sneak-thief.
- In the boys' bathroom they encounter Moaning Myrtle who was expecting some student, some sensitive boy.
- Slughorn seems to be doing his best to avoid Harry.
- Harry sees Goyle standing guard on the Marauder's Map. He speeds over to the Room of Requirement and scares Goyle away. Half an hour later Draco still has not come out. He encounters with Tonks, she came to see Dumbledore but Dumbledore was not in his office.
- The extra apparition training in Hogsmeade did well for Ron, he finally is improving.