Ha! In my family we play the Mafia game by the book but with alternative themes. My father-in-law used to work as a fireman, so I created the game of "Pyromaniac" for a family weekend trip. And for a party of one of my children, I rewrote the game towards "Wolf in sheep's clothes". They loved it (and would not understand the mafia references).

Hopefully the police is not alarmed by bits of paper with labels as "wolf" (mafia), "dog" (guardian angel), "shepherd" (detective) and "sheep" (civilian)...