<P> Jake actively stalks Oswald, renting apartments near those of the Oswalds . He begins to wonder if Oswald's only friend in Dallas, George de Mohrenschildt, may somehow be involved in the assassination, and thus hesitates to kill Oswald ahead of time . He thinks de Mohrenschildt is a CIA resource who is supposed to keep an eye on Oswald, but may also be egging Oswald on to kill first General Walker, then JFK . Jake resolves to wait until the Walker attempted assassination before killing Oswald . However, he is unable to learn certain facts and is prevented from accessing several opportunities to kill Oswald . </P> <P> Finally, the situation comes down to November 22, 1963 . With everything going wrong in order to prevent him from his date with destiny, he is only able to reach Oswald seconds before the fateful moment when Kennedy's motorcade drives through Dealey Plaza . Nevertheless, he successfully prevents Oswald from shooting JFK . In a rage, Oswald fires at Jake, ultimately killing Sadie, now Jake's fiancée, who came to help him . Oswald then is killed by outside fire . Jake is interrogated by the Dallas police and the FBI, who try to determine whether he was Oswald's accomplice . He has conversations with both the President and the First Lady . He is numb to all of it, because he has already resolved to travel to 2011 and then back to 1958 again, in order to save Sadie . He leaves Dallas by bus late on the night of Nov 22, and after he returns to New England, he learns that on Nov 25, a massive earthquake in Los Angeles has killed thousands . Jake realizes that it is a direct result of his actions . </P> <P> When he gets to the portal, the Yellow Card Man has been replaced by Zack Lang, a respectable looking man with a Green Card . Zack explains that traveling through the portal does not change the past, but creates multiple "time strings", stretching the bonds of reality . Guarding it is difficult, because the men dispatched to do so must keep myriad realities in their minds at all times (The cards function as a form of radiation detector; a green card indicates the agent is healthy, but as they deteriorate, the card changes to yellow, then to orange, and finally to black). The process is so stressful that it drives most agents to mental illness, alcoholism and eventually suicide, like Kyle, the previous agent . Zack begs Jake to set things right again, or reality itself will cease to exist . Jake steps back through the portal, eager to see what a world without a Kennedy assassination has become . Lisbon Falls is now in ruins . He meets a familiar looking man who turns out to be Harry Dunning, whose life he saved long ago . Not a brain - damaged janitor, he is a wheelchair - bound Vietnam vet who was paralyzed during the war . Furthermore, there are frequent, massive earthquakes everywhere . Harry tells Jake a concise history of the world between 1963 and 2011, and it's disturbing . For example, Vermont Yankee "went China Syndrome" in 1999, spreading radiation across New England and southern Quebec . Jake quickly returns to 1958 and finds Zack much worse for wear . He tells Jake he must now go back to 2011 (since all of Jake's changes are now undone), and ensure the portal is closed . Instead, Jake goes to a hotel and contemplates returning to Texas and Sadie . Ultimately, he returns to his own time, having changed nothing . Looking up old records on the Internet, Jake learns that Sadie survived the attack by her ex-husband which she had only survived before by his rescuing her with the assistance of Deacon who had another of Sadie's friends with him to assist in subduing the attacker . </P> <P> Jake goes back to Jodie, where Sadie is in her 80s and is being honored by the town with a celebration . In this timeline Sadie has no former memory of Jake, but she experiences deja vu when he speaks to her . The two share a dance . </P>

Significance of the yellow card man in 11/22/63
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