At night a mysterious event happens: Tales of young foals being whisked away in the night and never heard or seen again. Celestia has commissioned the Royal Guard and multiple detectives to seek out any information about what goes on at night. Many of the ponies suspect Princess Luna, but Celestia refuses to believe until she sees with her own eyes.
Main idea for this story comes from this: http://www.youtube.com/watch?v=6-3wp2VVhKQ&feature=g-like