Doctor Who to Rescue JFK in LIVE 50TH ANNIVERSARY SHOW

Enhancements in High Definition TV will tomorrow evening see actual events from the past change for the first time, as history and fiction merge. The BBC's Dr. Who hopes to travel back in real time in the first live broadcast of its kind.

The TARDIS will arrive on the day before the first episode of the time travel serial's broadcast, in 1963. It is thought that the current and eleventh incarnation of the Doctor (played by Matt Smith) will throw Lee Harvey Oswald from the window of the Texas Book Depository building, from where it is believed he assassinated President Kennedy - moments before the assassin carries out the deed. He will be assisted by the first Doctor (played by the late William Hartnell).

So how will the new technology enable time travel?

The fiftieth anniversary of the show will be broadcast live from 1,500 cinemas around the world - as well as on the BBC and numerous other channels in various territories - starting just before 8 pm GMT on Saturday night. As part of the TARDIS's sound effects, the cinemas will, for the first time, broadcast Fourth Generation sonic vibrations (provided by stentorian Who incarnation Tom Baker, at a Shepherd's Bush studio). The use of satellite technology will take into account the effects of time dilation above the Earth. Employing atomic clocks and real time updates will achieve the necessary synchronous amplifications from all of the theater houses and television networks.

The current Doctor (and whichever companions and characters accompany him to Dallas in November, 1963) can then assist the First Doctor in dispatching Oswald. A secondary storyline deals with current companion Clara Oswald, as she addresses her ancestors' personal history.

Online leaks have suggested that the attempt to thwart Lee Harvey Oswald's assassination of JFK will involve the sonic screwdriver being driven up and into Oswald from behind, and a quip including the term "book suppository" from the current Doctor as he falls to his death.

The events will be watched live - but half a century later - by the Obama administration from the White House's situation room.