There has been much discord of late between the law-creating and law-enforcing magistrates and the secretive guild of assassins who oppose what is, in their view, an iron-fisted rule of the populace. The Lord/Lady of the realm has invited all the high society nobles to a masquerade ball. Unbeknownst to the attendees, the guild of assassins plans to use this opportunity to kill the magistrates who will be in attendance.
Players are divided into two teams, and these teams are kept a secret. That is to say, any given player only knows which team they themselves are on; they do not know who else is on their team, or who is on the opposing team.