What would you want to see in such a thing?
0. Adventure/Session Name
1. Setting the Scene - a brief description, key notes/NPCs
2. The Event - introduces the conflict/quest - could be a singular or combination of the pillars.
3. Interesting Features - terrain/weather conditions, monsters, DCs...etc
4. Small Map (only if necessary)
5. Conclusion
Adventure Name:
We're the Rats
Setting the Scene
[Name] Two-story tavern. Mid-late evening. Bitterly cold winter's day. Handful of warmly dressed patrons. Dim light. Roaring fire. Staple diet is ale, hot soup and bread.
[Name] NPC and singular word descriptors. Innkeeper's dog. Social encounter which provides leads for characters' goals. Perhaps PCs notice girl.
The Event
A gust of wind bursts into the tavern, disturbing the common room as 3 shifty looking characters enter. The innkeeper's dog barks nervously at the strangers. The central figure, a scrawny man with a wickedly long nose and beady eyes sniffs the air in front of him and eyes out the crowd...searchingly. "She's here!" he cries out to his friends. They in turn, without missing a beat quickly bar the doors behind them. The innkeeper rushes out from the kitchen to witness what the rest of the tavern's patrons are seeing - the three individuals suddenly seem to undergo a violent and painful transformation....etc
long story short - wererats, slaughtering all within, attempting to reach to a young thin girl whose making her way to the top floor.
Interesting Features
Dim light except near the fire and on the second floor. Cover exists from tables and bar counter. Improvised weapons (chairs, glasses/mugs, plate of scalding soup, hot poker). Innkeeper locks kitchen door, grabs a hidden shortword behind the counter. Treat innkeeper's dog as ally. Wererats make for a straight line, leaping over/on tables, counters, climbing the banister...until a threat/obstacle presents itself.
Conclusion
If the wererats manage to corner the girl they attempt to grapple/pin her. In the attempt she changes into a wererat herself.
DM provides reason for her relationship with wererats. Perhaps opening up the possibility for further adventure.
Possible question - Why did the innkeeper's dog not initially bark at /suspect the wererat girl? Provide reasons. Investigation, Nature checks.
EDIT: The adventure is open-ended, PCs could save the girl and question her why 3 wererats were after her. Should they discover her secret they could kill her themselves or not. Have her arrested, which is what the innkeeper would (at minimum) prefer.