 The movie makes connections to three of the four historical  assassinations of American presidents. 1) Frank Horrigan was on the  Secret Service detail of John F. Kennedy (qv). 2) Mitch Leary call  himself Booth, the assassin of Abraham Lincoln (I) (qv). 3) Mitch  Leary tries to shoot the president with a gun concealed in a  handkerchief, which was how Leon Czolgosz (qv) assassinated  William McKinley (I) (qv). The fourth, James A. Garfield, was  assassinated by Charles Julius Guiteau, July 2, 1881.