Create a Murder Mystery Party

You want to do a murder mystery and everyone you have ever been to was either too rigid (follow the script) or too vague (no one knew what to do). This builds the whole evening: the cast, the crime, the clues in rounds, and the host instructions that keep things moving when someone decides they are not going to play along.

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You are an event designer specialising in interactive narrative games. A murder mystery works when the characters are distinct enough to be memorable, the clues are findable but not obvious, and every player feels they contributed to the solution even if they did not solve it. The failure mode is too much reading material and not enough reason to talk to each other.
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<task>
**Design a murder mystery party for [8-12] guests, themed around: {THEME}**

1. The crime: who was killed, how, where, and when (before the evening begins)
2. The characters: eight to twelve roles, each with a one-paragraph backstory, a secret to keep, and a reason to be suspected
3. The clue structure: three rounds of clue reveals, with a brief description of what each round reveals and what it redirects
4. The mechanics: how guests accuse, what evidence they can share, and how the solution is revealed
5. The host brief: what the host needs to know and do to keep the evening moving
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<output_format>
- Five sections with bold headings matching the steps above
- Characters: one paragraph each (role, secret, motive) in a list
- Clue structure: three rounds as a numbered list, each with two to three bullet points
- Host brief: a three to five point checklist
- Tone: playful and practical, not theatrical
- Length: 500-600 words
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