The Master mentally programmed UNIT Private Francis Cleary and sent him from the near future to prevent the assassination. This would change history and possibly enable the Cuban Missile Crisis to proceed in a way that would lead to a nuclear war. James Stevens, a journalist obsessed with the assassination attempt, went to 1963 using a time ring to stop Cleary. Stevens discovered the actual gunman who had killed Kennedy and recognised him as an older version of Stevens himself, travelling back from the future a second time. In order to preserve the course of history, in 1996, after writing a book revealing the truth, he used the time ring again to carry out the assassination. (PROSE: Who Killed Kennedy)
One of Kennedy's last official acts before his assassination was to order Moonbase Eisenhower to shoot down the US Rocket Lincoln, which had been stolen by the Sixth Doctor and Larisa Petrov. Although Kennedy did not rescind the order before his death, the moonbase's commanding officer General Paterson countermanded it when Petrov contacted him and proved that she was an American spy working in the Soviet Union. (AUDIO: 1963: The Space Race)
The Third Doctor mentioned to James Stevens in a telephone call that the prevention of the assassination would cause an historical embolism, which would result in the Doctor himself being erased from existence. (PROSE: Who Killed Kennedy)
Behind the scenes
The Kennedy assassination happened during the recording of an episode of The Daleks, interrupting shooting as the cast and crews learned of the news. A common rumour states that news coverage of the killing caused the interruption of the normal television schedule, too, so that on 23rd November, 1963, one day after the assassination, the first episode of the first Doctor Who story, An Unearthly Child, aired five minutes late; however it actually went out only ninety seconds later than scheduled. As the episode was not seen in parts of the country due to a power outage, it was rebroadcast the following week; it is often stated that it was replayed due to the assassination coverage, but this too has been debunked.
- The charity special NOTDWU: Dimensions in Time, which took place on 23 November in 1973, 1993 and 2013, includes a 1973 mention of the assassination having occurred ten years earlier.
- In Doctor Who and the Crusaders, a philosophical discussion at the beginning of the book makes note of the Kennedy assassination.