Reborn in a caste gated steampunk world, but to the lowest caste, Player A is furious that the higher castes are keeping secrets from the rest. Their last caste was archivist’s, which kept the secrets.
Player A’s character chooses to murder people to get the knowledge shared.
Player A uses 3D6 to choose what past lives they remember, and those are skillsets they use to commit these murders. (textiles, smithing, herbology, husbandry, woodworking, innkeepers)
Other players play Keepers Of The Law and Expert Citizens (choosing the caste of their expertise with a D6), and must catch Player A.
The first keeper’s (2nd player) is the senior partner & suspects that people are remembering past lives.
The second and junior keeper (3rd player) sees patterns in things.
The 4th & 5th players are expert witnesses called in by the keepers.
Any players beyond that play more keepers or experts.
Player A wins if they can commit all 6 murders without getting caught.
The other players win if they catch them prior to murder 6.
GM knows all & all players roll a die to see what number they are, but players only know who keepers and experts are.
This is built from the very very first plot idea that’s led to a far more complex and significantly different idea for a current work in progress.