@Hollander a movie on Giancana would very interesting with Joe Batters, JFK, Sinatra, The Maguire sisters, Johnny Roselli.... Sounds better then a fantasy about Capone in a syphillic daze.
Also a good story because it's about two close friends for decades and at the end one ordered the murder of the other. You could even throw in the Apalachin conference which Giancana attended. The meeting was reportedly originally set for Chicago.