1) Make a list of fifteen (15) characters and ten (10) locations, real or fictional. Keep it to yourself for the moment.
2) Ask your flist to post questions in the comments.
For example: "One and nine must stop eleven from destroying twenty. Do they succeed?"
"How likely are five and seven to have a passionate encounter in sixteen?"
"What would four do for fun in nineteen?"
3) After your flist has asked enough questions, round them up and answer them using the characters and locations you selected beforehand, then post them.
So, 1-15 are characters and 16-25 are locations. Just so we're clear. :D