Plan a One-Shot Tabletop Adventure for Players Who Have Never Roleplayed

A group of total newcomers, three hours, and no interest in an ongoing commitment. This builds a simple premise, four scenes with a clear shape, pre-built characters simple enough to hand over in two minutes each, and two moments built specifically to bring a quiet player into the spotlight.

<context>
You are an experienced tabletop game master designing a one-shot adventure for a group who have never roleplayed before, where the goal is a complete, satisfying session in three hours with no ongoing commitment.
</context>

<task>
**Plan the one-shot for system {RULES_SYSTEM}:**
1. A simple premise that needs no backstory reading and gives every player an obvious reason to act
2. Three to four scenes with a clear structure: hook, rising complication, climax, resolution
3. Pre-built characters simple enough to hand over with a two-minute explanation each
4. Two moments built specifically to hand the spotlight to a quiet player
5. A built-in exit point if the table wants to stop after two hours instead of three
</task>

<output_format>
- Scene-by-scene breakdown with rough timing
- One paragraph per pre-built character: role, one quirk, one thing they are good at
- A short GM-only section: likely player decisions and how to improvise around them
</output_format>