*** Welcome to piglix ***

The Key to Time

Doctor Who: The Key to Time
The Key to Time DVD cvr.jpg
Cover of the 2008 Region 2 DVD release
Starring
Country of origin United Kingdom
No. of stories 6
No. of episodes 26
Release
Original network BBC One
Original release 2 September 1978 (1978-09-02) – 24 February 1979 (1979-02-24)
Season chronology
← Previous
Season 15
Next →
Season 17
List of Doctor Who serials

The Key to Time is the umbrella title that links all six serials of the sixteenth season of Doctor Who. The arc was originally conceived by producer Graham Williams, who had proposed it as part of his application for the producer's job in 1976. The name refers to the powerful artefact for whose segments the Doctor, Romana and K-9 are searching during the season.

A figure calling himself the White Guardian commissions the Doctor and K9, assisted by a new companion, the Time Lady Romana, to find the six segments of the Key to Time, a cosmic artifact resembling a perfect cube that maintains the equilibrium of the universe. Since it is too powerful for any single being to possess, it has been split into six different segments and scattered across space and time, disguised by the raw elemental power within them into any shape or size. However, since the forces balancing the universe are so upset, the White Guardian needs to recover the segments of the Key to stop the universe so that he can restore the balance. The White Guardian also warns the Doctor of the Black Guardian who also wishes to obtain the Key to Time for his own purposes. In the final episode, the Black Guardian, disguised as the White Guardian, attempts to take the Key from the Doctor. However, the Doctor sees through the figure's charade and orders the segments of the Key to Time to once again become scattered across all of time and space, bar the sixth, which he reinstates as Princess Astra. Afterward, the Doctor decides to install a device called a randomiser into the TARDIS' navigation system for a period of time to make his following voyages unpredictable to evade the Black Guardian.

Tom Baker continued his role as The Fourth Doctor, and saw the introduction of Romana played by Mary Tamm. This season was the only one to feature Tamm as the first incarnation of Romana, as the second incarnation, played by Lalla Ward, began her run in the first serial of the next season (Destiny of the Daleks).


...
Wikipedia

...