Final answer:
Harry and Ron from the Harry Potter Series had accidentally locked the troll inside the women's restroom while attempting to warn Hermione.
Step-by-step explanation:
In the Harry Potter Series, more specifically the book Harry Potter and the Philosopher's Stone, Harry and Ron accidentally lock the troll inside the women's restroom.
The scene occurs on Halloween when the troll managed to get into the school. After hearing about it, Harry and Ron rush to warn Hermione, find her in the restroom, and unintentionally lock the troll inside with her. They end up having to rescue Hermione from the troll.
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