The Polyjuice Potion Plan and Its Consequences

Hermione, Harry, and Ron brew a complex Polyjuice Potion to infiltrate the Slytherin common room and question Draco Malfoy.

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The Idea Hatched

A Desperate Plan Hermione's Suggestion After the attacks, Hermione suggests using Polyjuice Potion to transform into Slytherins and interrogate Draco. She gets the recipe from the Restricted Section with Lockhart's help. The Ingredients The potion requires rare ingredients, including Boomslang skin and Bicorn horn, which must be stolen from Snape's stores. They plan a diversion in Potions class. The Risk Harry and Ron are hesitant, but Hermione's determination convinces them. The plan is dangerous and illegal, but they see it as their only chance to find the truth.

The Brewing and Theft

A Complicated Potion The Stealthy Infiltration During a Potions class, Harry uses a Filibuster firework to cause a distraction, allowing Hermione to sneak into Snape's office and steal the ingredients. The Brewing The potion is brewed in Moaning Myrtle's bathroom over several weeks. The trio visits regularly to add ingredients and stir. The potion finally becomes ready around Christmas. The Setback Hermione realizes they need hairs from the people they want to become. They decide to use Crabbe and Goyle, and Hermione uses a hair from Millicent Bulstrode, not knowing it's a cat hair.

The Infiltration and Failure

The Polyjuice Transformation Into Slytherin Harry and Ron successfully transform into Crabbe and Goyle and enter the Slytherin common room. They speak with Draco, but he reveals he is not the Heir and knows little. Hermione's Accident Hermione's potion turns her into a cat-human hybrid because she used a cat hair. She is forced to stay in the hospital wing for weeks. The plan is a partial failure. The Information Gained Despite the failure, they learn that the Chamber was opened fifty years ago by someone who was expelled, and that a Mudblood died. This confirms the legend and points to Hagrid's past.

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