they took down nucky johnson. >> it reminds me a lot of "boardwalk empire." >> sure.s that his great-uncle's undercover work isn't limited to bootleggers and gangsters. he also plays a key role in cracking the "crime of the century." it's all there in marty's strange inheritance. >> and i positively guarantee that this will forever change how this story will be viewed. >> here's another quiz question. more than 80 actors have portrayed al capone on tv or in the movies. which of these tough guys never did? the answer when we return. ♪ >> so, which actor never portrayed al capone on tv or in the movies? it's joe pesci. de niro played capone in "the untouchables," and robards in "the st. valentine's day massacre." ♪ >> marty dolan is unlocking the secrets of these original documents left behind by his great-uncle, mike malone, which tell the story of the crime-fighting division of the irs, called the t-men. >> they cleaned up the wild, wild west in chicago, took down the gangsters in new york city, cleaned up the politicians, and dealt with the hollywood elite. >> includ