Serial 4Z:
The Invasion Of Time
 
Working Title: The Invaders Of Time.
Starring: Tom Baker (The Fourth Doctor), Louise Jameson (Leela), John Leeson (Voice of K-9).
 
Plot
The Doctor returns to Gallifrey, having become President of the High Council following an illicit deal with aliens known as the Vardans. He has Leela exiled to the wastes beyond the Capitol, where she allies herself with outcast Time Lords living as savages. Leela believes the Doctor has turned traitor, but in fact he is masterminding an elaborate plan to unveil the identity of the Vardans' masters, and foil a scheme to invade Gallifrey itself.
 
Production
Graham Williams had been impressed by the Gallifreyan mythology Robert Holmes had devised for his Season Fourteen story The Deadly Assassin. For the conclusion of his first year as Doctor Who's producer, Williams wanted a follow-up story which would delve into the issue of Gallifreyans who were not Time Lords. He invited Holmes to write the story, but he had just left his job as the series' script editor and did not want to return to the programme so quickly. Consequently, the story was passed along to David Weir, with whom current script editor Anthony Read had worked on The Troubleshooters.
 
Following Williams' idea, Weir conceived a story called The Killer Cats Of Geng Singh (the exact spelling varies -- Gin Sengh, for example), introducing an intelligent feline race living on Gallifrey. Unfortunately, Weir was late in completing his drafts, and to the horror of Williams and Read, they were utterly unworkable, requiring abundant location filming and including inconceivable special effects sequences, like a stadium full of thousands of cat people. At the last minute, The Killer Cats was abandoned, and Williams and Read were forced to write a replacement story by themselves.
 
In the meantime, another serious problem had arisen, as it had become evident that a demarcation dispute would disrupt the autumn 1977 recording schedule. Because Christmas programming was of a higher priority, Serial 4Z would now only be granted one of its three studio sessions, as well as its location filming (and even this would eventually be slashed). Fortunately, it would be possible to dip into an emergency strike fund, providing Doctor Who with two weeks' worth of Outside Broadcast (OB) taping. The BBC, however, suggested that Williams might instead abandon the serial altogether, and save the money for Season Sixteen. Williams was keen on preserving his finale, however, and decided to proceed forward.
 
Based on an outline he and Williams had put together over a weekend, Read wrote the first draft of The Invasion Of Time (possibly also titled The Invaders Of Time) in just a fortnight. Robert Holmes provided some advice to Read by telephone during this period. He also gave permission for his creations, the Sontarans, to be used in the serial. A new villain was needed to replace the eponymous race from The Cat People, since The Invasion Of Time was forbidden from reusing any story elements created by Weir. Read then handed the story over to Williams, who heavily rewrote the scripts during four sleepless days.
 
Because it would be seen as inappropriate for a series' producer and script editor to receive credit for a script, Williams and Read decided to transmit The Invasion Of Time under the pseudonym "Richard Thomas" (named after Williams' young son), despite the fact that the Writers' Guild had agreed that the situation surrounding the serial was exceptional. Head of Serials Graeme MacDonald, however, ordered that the standard BBC alias of "David Agnew" be used.
 
A final wrinkle for The Invasion Of Time was that it had to write out the character of Leela. Although Louise Jameson had, for several months, been firm that she would be departing Doctor Who at the year's end, Williams still held out hope that she might change her mind (despite his own growing realisation that Leela's potential had been all but exhausted). Ultimately, the character's departure was a last minute addition to the scripts, and hence was given very little consideration. Leela's out-of-character romance with the Chancellery Guard Andred was an enormous disappointment to Jameson, who would have preferred to see Leela killed off. Williams and Read had contemplated this (as they had on The Sun Makers), but decided that it would be too traumatic for the series' younger viewers, and a pessimistic way to end the season. To try to make the relationship more plausible, Jameson and Chris Tranchell, who played Andred, contrived additional moments of tenderness between their characters for recording.
 
Also written out in The Invasion Of Time was K-9, of a fashion. Although the robot dog had been heavily refurbished in between first and second appearances (The Invisible Enemy and The Sun Makers), it was decided to start from scratch between seasons and build a totally new model. Hence the end of The Invasion Of Time saw the introduction of a "Mark II" K-9. Meanwhile, in addition to the various exits, The Invasion Of Time also saw the return of one character. Holmes had agreed to let the production team use the character Borusa (now a Chancellor) he had invented for The Deadly Assassin. Here, however, John Arnatt would replace original actor Angus Mackay, who was unavailable.
 
Because of all the problems associated with The Invasion Of Time, Williams intentionally sought out a veteran director who would be able to assuage on-set tensions and get the serial completed. This was Gerald Blake, working on his second and last Doctor Who adventure (the first had been The Abominable Snowmen more than a decade earlier). Blake died in April 1991. The various production difficulties meant that The Invasion Of Time was made in an unusual order, starting with the single studio session from Sunday November 6th to Tuesday the 8th. Then just a day and a half of filming took place on the 14th and 15th, at the Laporte Industries sand pit in Surrey. Finally, the OB work was carried out, beginning on the 15th and continuing, with several interruptions, until December 16th. As with Underworld, The Invasion Of Time was allocated gallery-only time to finish the special effects work, on the 18th and 21st.
 
In addition to ending production on Season Fifteen, December 16th marked Louise Jameson's final work on Doctor Who. She would go on to star in several stage and television productions, including the series The Omega Factor, Tenko and Bergerac, and would also develop a career teaching drama. Jameson returned to Doctor Who for Dimensions In Time in 1993. Her final regular episode, part six of The Invasion Of Time, aired on March 11th, 1978, bringing Doctor Who's tumultuous fifteenth season to a close.