Doctor Who (season 16)

The sixteenth season of British science fiction television series Doctor Who, known collectively as The Key to Time, began on 2 September 1978 with The Ribos Operation, and ended with The Armageddon Factor. 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.[1] The name refers to the powerful artefact, the segments of which are what the Fourth Doctor and his companions, Romana and K9, search for during the season.

Doctor Who
Season 16
Cover of the 2008 Region 2 DVD release
Starring	Tom Baker Mary Tamm John Leeson
Country of origin	United Kingdom
No. of stories	6
No. of episodes	26
Release
Original network	BBC1
Original release	2 September 1978 – 24 February 1979
Season chronology

Synopsis

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.

The six segments

1. The first segment is disguised as a lump of Jethrik on the planet Ribos.
2. The second is the planet Calufrax, shrunk to miniature size by the space-hopping pirate planet Zanak.
3. The third is the Great Seal of Diplos, which has been stolen by a criminal of that planet.
4. The fourth is part of a statue on the planet Tara.
5. The fifth has been consumed by the squid Kroll, causing it to turn into a gigantic monster.
6. The final segment is a female humanoid – Princess Astra.

Casting

Main cast

• Tom Baker as the Fourth Doctor
• Mary Tamm as Romana
• John Leeson as Voice of K9

Guest Cast

• Valentine Dyall as 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 (who also appeared in this season as Princess Astra), began her run in the first serial of the next season (Destiny of the Daleks).

Serials

Douglas Adams took over as script editor from Anthony Read for The Armageddon Factor. Season 16 consists of one long story arc encompassing six separate, linked stories.

Story	Serial	Serial title	Episode titles	Directed by	Written by	Original air date	Prod. code	UK viewers (millions) [2]	AI [2]
98	1	The Ribos Operation	"Part One"	George Spenton-Foster	Robert Holmes	2 September 1978	5A	8.3	59
			"Part Two"	George Spenton-Foster	Robert Holmes	9 September 1978	5A	8.1	—
			"Part Three"	George Spenton-Foster	Robert Holmes	16 September 1978	5A	7.9	—
			"Part Four"	George Spenton-Foster	Robert Holmes	23 September 1978	5A	8.2	67
The Doctor is recruited by the White Guardian to seek the six segments of the Key to Time. The quest for the first segment takes them to Ribos, a medieval planet that galactic confidence trickster Garron is trying to sell to the Graff Vynda-K.
99	2	The Pirate Planet	"Part One"	Pennant Roberts	Douglas Adams	30 September 1978	5B	9.1	61
			"Part Two"	Pennant Roberts	Douglas Adams	7 October 1978	5B	7.4	—
			"Part Three"	Pennant Roberts	Douglas Adams	14 October 1978	5B	8.2	64
			"Part Four"	Pennant Roberts	Douglas Adams	21 October 1978	5B	8.4	64
The quest for the second segment takes them to the planet Zanak, which has been hollowed out and fitted with hyperspace engines, allowing its insane half-robot Captain to materialise it around other smaller planets and plunder their resources.
100	3	The Stones of Blood	"Part One"	Darrol Blake	David Fisher	28 October 1978	5C	8.6	—
			"Part Two"	Darrol Blake	David Fisher	4 November 1978	5C	6.6	—
			"Part Three"	Darrol Blake	David Fisher	11 November 1978	5C	9.3	—
			"Part Four"	Darrol Blake	David Fisher	18 November 1978	5C	7.6	67
The quest for the third segment takes them to Earth, where an ancient criminal who stole the segment disguises herself as the Celtic goddess Cailleach.
101	4	The Androids of Tara	"Part One"	Michael Hayes	David Fisher	25 November 1978	5D	9.5	—
			"Part Two"	Michael Hayes	David Fisher	2 December 1978	5D	10.1	65
			"Part Three"	Michael Hayes	David Fisher	9 December 1978	5D	8.9	—
			"Part Four"	Michael Hayes	David Fisher	16 December 1978	5D	9.0	66
The quest for the fourth segment takes them to the planet Tara. The Fourth Doctor and Romana find themselves embroiled in the political games of the planet Tara, where doubles, android or otherwise, complicate the coronation of Prince Reynart.
102	5	The Power of Kroll	"Part One"	Norman Stewart	Robert Holmes	23 December 1978	5E	6.5	—
			"Part Two"	Norman Stewart	Robert Holmes	30 December 1978	5E	12.4	—
			"Part Three"	Norman Stewart	Robert Holmes	6 January 1979	5E	8.9	—
			"Part Four"	Norman Stewart	Robert Holmes	13 January 1979	5E	9.9	63
The quest for the fifth segment takes them to the third moon of Delta Magna, caught in the middle of a dispute between the crew of a methane refinery and the natives (known as 'Swampies').
103	6	The Armageddon Factor	"Part One"	Michael Hayes	Bob Baker and Dave Martin	20 January 1979	5F	7.5	65
			"Part Two"	Michael Hayes	Bob Baker and Dave Martin	27 January 1979	5F	8.8	—
			"Part Three"	Michael Hayes	Bob Baker and Dave Martin	3 February 1979	5F	7.8	—
			"Part Four"	Michael Hayes	Bob Baker and Dave Martin	10 February 1979	5F	8.6	—
			"Part Five"	Michael Hayes	Bob Baker and Dave Martin	17 February 1979	5F	8.6	—
			"Part Six"	Michael Hayes	Bob Baker and Dave Martin	24 February 1979	5F	9.6	66
The quest for the sixth and final segment takes them to Atrios, a world at war with its planetary neighbour Zeos. But the Black Guardian is closing in.

Broadcast

The Key to Time was broadcast from 2 September 1978 to 24 February 1979.

Home media

VHS releases

Season	Story no.	Serial name	Number and duration of episodes	R2 release date	R4 release date	R1 release date
16	098	The Ribos Operation	4 x 25 min	April 1995	June 1995	September 1996
	099	The Pirate Planet	4 x 25 min	April 1995	June 1995	September 1996
	100	The Stones of Blood	4 x 25 min	May 1995	July 1995	March 1996
	101	The Androids of Tara	4 x 25 min	May 1995	July 1995	March 1996
	102	The Power of Kroll	4 x 25 min	June 1995	August 1995	September 1996
	104	The Armageddon Factor	6 x 25 min	June 1995	August 1995	September 1996

DVD and Blu-ray releases

Season	Story no.	Serial name	Number and duration of episodes	R2 release date	R4 release date	R1 release date
16	098–103	The Key to Time[lower-alpha 1]	26 × 25 min.	N/A	N/A	1 October 2002[3]
		The Key to Time: The Ribos Operation The Pirate Planet The Stones of Blood The Androids of Tara The Power of Kroll The Armageddon Factor	26 × 25 min.[lower-alpha 2]	24 September 2007[lower-alpha 3][4] 16 November 2009[lower-alpha 4][5]	7 November 2007[6]	3 March 2009[7]

1. Stories available in Region 1 only, with minimal restoration and extras (individually or as a box set).
2. Special edition. Known collectively as The Key to Time. Only available as a box set in Regions 2 and 4. Stories available individually or as a box set in Region 1. All serials contain four episodes each, apart from The Armageddon Factor, which has six episodes.
3. Limited release.
4. Re-release.

In print

Serial name	Novelisation title	Author	First published
The Ribos Operation	Doctor Who and the Ribos Operation	Ian Marter	11 December 1979
The Pirate Planet	The Pirate Planet	James Goss	5 January 2017[8][9][10]
The Stones of Blood	Doctor Who and the Stones of Blood	Terrance Dicks	20 March 1980
The Androids of Tara	Doctor Who and the Androids of Tara	Terrance Dicks	24 April 1980
The Power of Kroll	Doctor Who and the Power of Kroll	Terrance Dicks	26 May 1980
The Armageddon Factor	Doctor Who and the Armageddon Factor	Terrance Dicks	26 June 1980

References

1. "Season 16". Doctor Who Classic Episode Guide. BBC. Retrieved 10 August 2007.
2. "Ratings Guide". Doctor Who News. Retrieved 27 December 2014.
3. "Doctor Who - The Key to Time Collection". 1 October 2002. Retrieved 16 November 2017 – via Amazon.
4. "Doctor Who: Key to Time". Retrieved 16 November 2017 – via Amazon.
5. "Doctor Who - The Key to Time Box Set". 16 November 2009. Retrieved 16 November 2017 – via Amazon.
6. "Doctor Who The Key To Time Box Set by BBC - Shop Online for Movies, DVDs in Australia". Fishpond. Retrieved 16 November 2017.
7. "Doctor Who: The Key to Time". 3 March 2009. Retrieved 16 November 2017 – via Amazon.
8. Adams, Douglas; Goss, James (5 January 2017). "Doctor Who: The Pirate Planet". BBC Digital. Retrieved 25 August 2016 – via Amazon.
9. "Gallifrey Guardian". Doctor Who Magazine. Tunbridge Wells: Panini UK Ltd (486): 7. April 2015.
10. Dave Golder (30 April 2015). "Doctor Who Pirate Planet Novelisation Announced". GamesRadar+.