I have a secret society called the Peacekeepers, who seek out and imprison anyone in the town who has anything at all magical about them. Any race other than human, dwarf, and halfling is suspect. The public display of any magical power or talent is cause for immediate arrest. Even owning a magic item of any sort will earn you a room in their special prison. It's been this way for as long as anyone native to the town can remember - it's just a part of life. Traders in the area have learned the hard way, so the most common victims are travelers and adventurers.
My husband was helping me brainstorm, and suggested that perhaps the prisoners get a chance to earn their freedom (a la "Running Man" - old Arnold Schwarzenegger movie). I liked the idea, and decided the prisoners would be chosen by a lottery system - completely random. This is where my ideas get a little foggy. Why would the Peacekeepers imprison these characters, only to later offer them a chance to earn their freedom? Is their quest some local menace? Or is there something even more devious? Could their perceived quest for freedom merely be a test to propel them into some further nefarious Peacekeeper plot?
Thanks in advance for any and all feedback.