"Family secrets emerge as a best-selling author dives into the history of the mob in small-town America. Johnstown, Pennsylvania, a city "in its brawny postwar prime," is where "Little Joe" Regino and Russ Shorto build a local gambling empire on the earnings of factory workers for whom placing a bet-on a horse or pool game, pinball or "tip seal"-is their best shot at the American dream. Decades later, Russell Shorto grew up knowing that his grandfather...