. >> t-men like michael francis malone, born jersey city, new jersey, 1893. >> poor irish from the streetsrsey city. he learned italian, yiddish, greek, a bit of spanish, and, obviously, hobokenese and jerseyese. >> when mike's 20, he joins the army, serving with the flying cadet squadron during world war i. after he returned stateside, he gets married and starts a family. then tragedy strikes. >> two of his children died. >> oh, my. >> after the death of their second child, there was an estrangement that never really got better. he became this nomad and put his life at risk. >> mike joins the bureau of investigation, the precursor to the fbi. he quickly makes a name for himself, then jumps agencies to the t-men. malone's new job -- go undercover with the mob. that's pretty risky stuff. >> it was extremely risky. he really -- his life was put in danger. >> in 1929, malone is put on the case to take down public enemy number one, al capone, the brutal chicago mob boss known as the original scarface. malone leaves behind notes from his undercover work. marty shares them with irs agent paul ca