November 22, 1963. JFK is in Texas to mend fences between the liberal and conservative wings of the state's Democratic Party prior to beginning his re-election campaign. Lee Harvey Oswald assembles a rifle in his Dallas home. All that follows plays out against the backdrop of this, the last day of Jack's life. A flashback to three months earlier reveals Jack and Jackie bonding in a way they never have before, united by mutual grief over the loss of their newborn child. Meanwhile, Bobby is informed of evidence romantically linking Jack to the late Marilyn Monroe who, a year earlier, sung JFK Happy Birthday at Madison Square Garden, then told Bobby she wanted to have John's baby. Now it's up to Bobby to deal with the incriminating evidence - which prompts a heated argument between him and Ethel. As we return to present day, the countdown to tragedy continues. Jack and Jackie depart Fort Worth for Dallas, while Oswald quietly hides the rifle on the sixth floor of the Texas Schoolbook Depository, overlooking Dealey Plaza.