The events in parts one and two of "The Unhired Assassin" are based on real facts...to a point. In other words, much of what you see in the show did actually occur BUT much of it also is conjecture and fabrication in order to entertain. So, do NOT take this as a history lesson.
Here are the true facts. A crazy guy named Joe Zangara (Joe Mantell) did try to kill President Roosevelt in Miami....or at least folks think his intended victim was the newly elected president. Instead, Mayor Anton Cermak (Robert Middleton) and several others got shot as they stood near the president. Two (including Cermak) died. However, the rest of the episode is complete conjecture as they seem to say in "The Untouchables" that Cermak was the intended victim--an enemy of Frank Nitti and organized crime. Who came up with this unsupported theory? The show's narrator, Walter Winchell...and her in the program they are repeating Winchell's theory decades later. Oh, and throughout the show the mobsters keep referring to Cermak as a Bulgarian...though he was from an area now that is part of the Czech Republic (about 700-800 miles apart).
Despite the many historical inaccuracies, this is a very exciting two-parter. The scene where Akins' character arranges to blow up a man is pretty amazing as is the first attempt on Cermak's life...complete with dying man firing a machine gun as he spins to his death! Additionally, the cast of thugs is impressive. Aside from Bruce Gordon as Nitti, you've also got Claude Akins as a particularly nasty and stupid gunman, Lee Van Cleef, Richard Deacon (yes, 'Mel Cooley' is a gangster!) and Frank DeKova. Middleton's rendition of Cermak was a bit sappy and difficult to believe at times.