I got two ideas that would make a good film.
1. The mobs involvement in the sex industry during the 70s and 80s. Could possibly focus on time square at the time. Could have characters based on the perainos who financed deep throat.Apparently they ended up getting shot which would be a good ending for a film. Probably not be the most flattering portrayal of the mafia still an interesting story.

2.Do one on the philadelphia underworld in which the story of both the italian and black mafia intertwine as their were certain instances where both groups had members working together but also so sort of came apart at the same time.