Season 16

From Tardis Wiki, the free Doctor Who reference

Season 16 of Doctor Who, also referred to as The Key to Time, ran from 2 September 1978 to 24 February 1979. It starred Tom Baker as the Fourth Doctor, Mary Tamm as Romana I and John Leeson as K9 Mark II. The season opened with The Ribos Operation and concluded with The Armageddon Factor.


It consisted of six serials comprised of twenty-six episodes. This season saw the introduction of the Black and White Guardians as well as the companion Romana I who became the first Time Lady companion since Susan. This season is sometimes colloquially known as The Key to Time season after the story arc involving the Key to Time. Although not the first season to consist of linked stories (Season 8 in 1971 was the first, as all the stories that year featured the Master), it was the first to be recognised as having a series-long arc. Although multi-serial arcs would occur again, such a full-season experiment wouldn't be attempted again until Season 23. The arc has a number of similarities to the Season 1 story The Keys of Marinus. The storyline was originally proposed for Season 15, but it required more planning.[1]

Season 16 marked a triple milestone for Doctor Who: the hundredth story (The Stones of Blood), the five-hundredth episode (episode 1 of The Armageddon Factor) and the fifteenth anniversary of the first broadcast, on 23 November 1978.

A number of publicity photos for the season show Tom Baker sporting a very obvious bandage on his upper lip; this was due to his being bit by a dog shortly before filming for the season began. The resulting lip injury is visible to varying degrees throughout the season.

In 2002 (Region 1) it became the first Doctor Who season to be released to DVD in its entirety in a single box set; it remained the only "classic series" season to be available as a single set until the release of Season 23, The Trial of a Time Lord to DVD in 2008.

Tom Baker decided to leave by the end of this season, but he was persuaded to stay.[2]

Television stories[[edit]]

# Title Writer Episodes Notes
1 The Ribos Operation Robert Holmes 4 First appearance of Romana and the White Guardian. Beginning of the Key to Time quest.
2 The Pirate Planet Douglas Adams 4 First story to written by Douglas Adams, and the only televised story where he received sole credit.
3 The Stones of Blood David Fisher 4 Marks Doctor Who's one hundredth television story. Part four aired during the fifteenth anniversary of the series. First story to be written by David Fisher.
4 The Androids of Tara 4
5 The Power of Kroll Robert Holmes 4
6 The Armageddon Factor Bob Baker
Dave Martin
6 Final appearance of Romana I. First appearance of the Black Guardian. Final story on which Anthony Read was script editor and the final story to be written by Dave Martin. Conclusion to the Key to Time quest.





Stories set before this season[[edit]]

The following stories are the known stories set between Season 15 finale The Invasion of Time and Season 16 opener The Ribos Operation:


to be completed

Stories set during this season[[edit]]


Short Stories[[edit]]



Adaptations and merchandising[[edit]]

Home media[[edit]]

VHS releases[[edit]]

DVD & Blu-ray releases[[edit]]

This entire season was released with minimal restoration and extras only in Region 1 as a box set or individually on 1 October 2002. A limited edition box set with full restoration and expanded extras was released in Region 2 on 24 September 2007. This limited edition set was later issued in Region 4 on 7 November 2007, in Region 1 on 3 March 2009 as a Special Edition release (these were also available individually), and in Region 2 on 16 November 2009 as a non-limited re-release.

Serial name Number and duration
of episodes
R2 release date R4 release date R1 release date
The Key to Time 26 × 25 min. N/A N/A 1 October 2002
The Key to Time:

The Ribos Operation (4 episodes)
The Pirate Planet (4 episodes)
The Stones of Blood (4 episodes)
The Androids of Tara (4 episodes)
The Power of Kroll (4 episodes)
The Armageddon Factor (6 episodes)

Only available in The Key to Time box set in Regions 2 and 4.
Available individually or in the box set in Region 1.

26 × 25 min. 27 September 2007
(Limited release)
16 November 2009
7 November 2007 3 March 2009

Download/streaming availability[[edit]]

Serial name Amazon Video iTunes
The Ribos Operation (4 episodes)
The Pirate Planet (4 episodes)
The Stones of Blood (4 episodes)
The Androids of Tara (4 episodes)
The Power of Kroll (4 episodes)
The Armageddon Factor (6 episodes)


Target Books was unable to come to an agreement with Douglas Adams to novelise his script, The Pirate Planet. It was finally adapted by BBC Books in 2017.


External links[[edit]]