In a small inn (the more remote the better), a man turns up dead. There are no wounds on his body what-so-ever, and he aboslutely reeks of garlic.
The man died of a curse that forced him to eat a clove of garlic a day or suffer the penalty. This gets really interesting if the body somehow appears on top of a someone the villagers are suspcious of.
A village where everyone goes blind sometime during puberty. What could be causing this? Perhaps something in their diet. Or some malignant gene. How would an entire village where only young childen can see function?