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The UNIT Timeline – Paradox or Wormhole?

Updated: Jan 8, 2022

It is common knowledge that the UNIT timeline is one big wibbly-wobbly timey wimey mess, paradox and wormhole. Various plot holes, contradictions, and inconsistencies throughout the 70s and 80s do provide a challenge for anyone to draw up a timeline in which the UNIT stories take place. At times it would seem almost impossible to do so, since there is no easy answer, and any answer drawn up is simply speculation.

However, there are various clues which do help form some sort of continuity, and in themselves are helpful to place the UNIT stories in some sort of timeline. That being said there are also a fair share of missing or elusive pieces of background information which counteract the helpful clues, and often or not, take you back to square one. Perhaps that the whole point of the UNIT timeline is that, nobody knows for certain exactly when it take places, maybe The Third and Fourth Doctors (Jon Pertwee and Tom Baker) don’t even know themselves. But this blog is going to have a stab at it, and answer the question once and for all, when does the UNIT timeline take place? First let’s take a look at what we know: consistencies or inconsistencies the same.

First, and foremost, it is firmly established that the UNIT stories shown in broadcast order occur chronologically. Throughout The Third Doctor’s tenure various characters refer to events that took place in the previous adventure. For example in The Ambassadors of Death (1970), The Third Doctor is still furious with The Brigadier (Nicholas Courtney) for destroying the Silurian base in Doctor Who and the Silurians (1970), and when The Master is arrested at the end of The Daemons (1971) he is incarcerated during The Sea Devils (1972). During The Invasion (1968), Sergeant Benton (John Levene) is a corporal, but during the Third Doctor’s tenure is a Sergeant. The Second Doctor (Patrick Troughton) addresses ‘Sergeant Benton’ as Corporal during The Three Doctors (1972-73) because The Second Doctor has been plucked out of his own time stream and does not know (at this point) that Sergeant Benton has been promoted. Also during The Daemons Sergeant Benton (John Levene) links the Daemons to the Autons and the Cybermen, so the events of The Invasion (1968) have already happened. These simple clues, although somewhat obvious, provide a major breakthrough to draw up a possible UNIT timeline.

Secondly, the Doctor Who universe occurs in our universe – ‘somewhat’. The Doctor will often refer to adventures where he meet historical figures, Sir Walter Raleigh (The Mind of Evil) etc. But then again the show has always been a little vague about who the Prime Minister is during specific episodes. During The Green Death (1973), the Prime Minister is a man simply referred to as Sir Jeremy (Brychan Powell) – a nod towards Sir Jeremy Thorpe(?), and during Terror of the Zygons (1975), the Prime Minister is addressed as ‘she’ -possibly Margaret Thatcher(?). The revived series has done a similar thing where the ‘dead’ Prime Minister in Aliens of London (2005), Harriet Jones (Penelope Wilton) and Brian Green (Nicholas Farrell), the Prime Minister during the 456 Crisis in Torchwood: Children of Earth, are all fictional.

Thirdly, there have been some plot holes which mess up the timeline. The events of The Web of Fear (1968) and The Invasion supposedlytake place in 1975 and 1979 respectively. The Brigadier appears both times, and is still heading UNIT. However during Mawdryn Undead (1983), it is revealed that The Brigadier retired in 1977 and is still teaching Maths in 1983, without any mention of him returning to UNIT for brief spells. This is perhaps the first major problem when it comes to placing the UNIT stories on a timeline. So do The Web of Fear and The Invasion really take place in 1975 and 1979? Or do they take place at some alternative date?

Fourthly, throughout The Third Doctor tenure it is suggested that the UNIT stories take place in the near future– but what does that mean? If The Daemons occurs after The Invasion, this must mean that The Daemons takes place sometime around or after 1979 (if the date for The Invasion is correct), at least 8 or more years in the future after the episode’s broadcast. First we must pose a question, would 8+ years be considered to be the near future from any particular date? Possibly. However, the concept of the ‘near future’ for most would probably mean 1 or 2 years, since it is quite impossible to imagine what the future would look like in a longer period of time. Almost a decade in the future is a little bit of stretch to be considered as the ‘near future’. For a student who is about to start their last year at Primary School, 8-10 years would span their (maximum 6 years at High School) and (maximum 4 years at University) for example, a big gap to call near future surely. Then again ….

Fifthly, the show has given us brief glimpses of the future to come but at a cost. During The Daemons (again), a TV Crew are clearly operating equipment from BBC3. From a viewers’ point-of-view in 1971, BBC3 did not exist, nor will it for 30 years! So does that mean The Daemons is actually set in or around 2003 – no! No it doesn’t. This little glimpse of the future is perhaps a stretch too far.

At the moment it would look like there is not much leeway in terms of drawing a UNIT Timeline, but there is a lot we can take from the five points above. The next step (the logical step) would be to analyse the personal lives and timelines of the Third Doctor’s companions – Liz Shaw (Caroline John), Jo Grant (Katy Manning), and Sarah Jane Smith (Elisabeth Sladen). All three companion’s lives both prior and after meeting and travelling with The Doctor are equal, and could provide vital keys in placing the UNIT stories in a timeline. Let’s start with Liz Shaw …

Liz Shaw was introduced in Spearhead from Space (1970), personally recruited to join UNIT by The Brigadier whilst carrying out research at Cambridge University. Now according to PROSE: The Devil Goblins from Neptune, Liz was born in 1943 and AUDIO: The Blue Tooth suggests that Liz joined UNIT in her mid-twenties.

During Liz Shaw’s introduction the Brigadier makes it clear that Liz is ‘an expert in meteorites’ and has ‘degrees in medicine, physics and a dozen other subjects’. Liz Shaw previously stated, ‘I have an important research programme going ahead at Cambridge’. Now this important. This means that Liz has graduated from University, completed her post-graduate qualifications, and holds a PhD. Now a lot of this may seem irrelevant; but it gives us the basis of estimating Liz’s age at the moment of her introduction. Throughout the Doctor Who universe (books, comics, TV serials etc.) there is no mention of Liz being a child genius (skipping grades, studying at a school for gifted children etc). So it’s probably safe to presume that Liz started University at the age of 17/18 which means she would have completed her undergraduate degree at 21/22. So the next question is, when was Liz born?

So if PROSE: The Devil Goblins from Neptune is correct, and Liz was born in 1943, she would have started University around about 1960/61, and would have graduated in 1964/1965. Now as AUDIO: The Blue Tooth suggests Liz joined UNIT in her mid-twenties so 24-26 which would put her arrival at UNIT in around 1967/68. Now, this seems unlikely (unless of course the Doctor Who universe has a different meaning of what mid-twenties means), since Liz would have achieved her twelve degrees in less than 3 years after graduating. Now, maybe Liz did achieve her twelve degrees in roughly 3 years, if she studied full-time, never took a day off from studying, spend every hour of every day …. that would probably do a lot of damage to the mental health (again Liz was no child genius). But it could be possible. Liz also mentioned that she was leading a research programme at Cambridge – but leading who? Students? Graduates? Professors? Who? Would Liz really be put in charge of research programmes being so young, and so close to her graduation?

Let’s presume (to put another argument on the table) for a minute that Liz Shaw and Caroline John are supposed to be the same age. This would mean that both Caroline and Liz would be 29 at the time of the broadcast of Spearhead from Space in 1970 – Caroline John was born in September 1940 and Spearhead from Space was broadcast in January 1970. Presuming that Liz was born in 1940 (and not 1943), this time she would have begun University in 1957/1958 and graduated in 1961/1962. Now if she joined UNIT in her mid-twenties (we would still run into the same problems) – Liz would have achieved everything mentioned in Spearhead from Space in roughly 3 years. It’s probably safe to presume that Liz was a little bit older when she joined UNIT. So presuming that Liz and Caroline John are the same age (with a birth year of 1940), Liz joined UNIT at 29 years of age. Establishing Liz’s age at 29 would mean she spent 7 years (and not 3) achieving all of her degrees. Now whilst this is still a stretch, it makes more sense than 3, for reasons given previously. This means that Liz arrived at UNIT in roughly 1969, but when did she leave?

Liz’s departure off-screen in Terror of the Autons (1971) explains that Liz went back to Cambridge University – possibly to continue her research and The Doctor is visibly annoyed. Why? Maybe because Liz (a talented, smart, resourceful scientist) reminded The Doctor of himself (but younger). Liz’s departure is also later mentioned in four separate stories all in short story and prose formats (we’re not going to go there believe me), but let’s concentrated on PROSE: The Scales of Injustice. SPOILER WARNING: During the story a young teenager Marc Marshall is one of many victims of the Silurians, which greatly upsets Liz, but not so much The Doctor. Now seeing the death of a young teenager was an emotional affair for Liz Shaw, and her departure swiftly followed.

Now whilst there isn’t an overtly elaborate reasoning behind Liz leaving UNIT, perhaps at the heart of it, Liz probably didn’t want to let go of amazing opportunities at Cambridge University. If she was indeed put in charge of research experiments at the Cambridge University, then she would want to make sure that she would make the most of such opportunities, would she really stay away from Cambridge University for a long period of time? So how long did Liz spend at UNIT? To answer the question let’s continue with the second companion to the Third Doctor, Jo Grant.

Jo Grant was introduced in Terror of the Autons, a little while after the events of Inferno (1970). Now the timeline of Jo’s life is a little more complicated than Liz’s, and they all centre around her swansong The Green Death (1973).

During The Green Death Jo meets Professor Clifford Jones (Stewart Bevan), and the pair eventually plan to get married at the end of the serial. Now Jo and The Doctor never see each other again, after this, that is until the pair cross paths again in The Sarah Jane Adventures 2-parter Death of the Doctor (2010). The Doctor asks Jo, ‘Last time I saw you, Jo Grant, you were, what, 21, 22?’ So that forms the basis of determining what age Jo was when she left The Doctor.

Let’s presume, that just like Liz Shaw, Jo Grant and Katy Manning are the same age. The pair of them would have been born in 1946 – Katy Manning’s birth year, and if Jo left The Doctor at 21/22 years of age, she would have left The Doctor in 1967/1968. Death of the Doctor is set in 2010 which would mean that 42/43 years have passed since Jo and The Doctor last saw each other. Now while entirely possible, it’s not the best solution. If Jo left UNIT in 1968 this would means that her time with The Doctor possibly takes place before Liz’s time, which simply can’t be the case. Since the UNIT stories take place chronologically. So when was Jo born then?

According to PROSE: Carpenter/Butterfly/Baronet Jo’s birth year is 1951. So if Jo was 21 or 22 when she left UNIT her departure would roughly occur in 1972/1973 – a little while after Liz’s arrival and departure from UNIT. 1972 would seem like a good year to place things, but just to be sure …

According to AUDIO: The Other Woman places Jo’s birth year as 1961. So again, if Jo was 21 or 22 at the time of her departure, that would place things in 1981/1982. This can’t be the case either since by the early 1980s, the Brigadier had retired to become a Maths Teacher, and never returned to duty. So AUDIO: The Other Woman can’t be used as a reliable source of information. So it’s safe to presume that Jo was born in 1951.

To firmly establish Jo’s time at UNIT further we need to take a look at Jo’s school days, and the various remarks The Doctor makes about Jo failing various school subjects. When Jo first arrived at UNIT she remarks that she took General Science at A Level, but didn’t say anything about passing. During The Daemons The Doctor deduces that Jo failed Latin as well when she failed to see that Magister was the Latin word for Master. Now yes these pieces of information are probably just general observations, but do they provide an insight as to when Jo attended school. Latin itself was a core subject during the first half of the twentieth century in many public and probably private schools. So if Jo was born in 1951 then she would have started school in 1955/56. So this means that Jo would have been attending school in the dying days of Latin being taught in main stream education. So it is possible that Jo learned Latin just as the subject was being phased out from the curriculum.

Despite failing General Science and Latin (possibly), Jo display basic skills in understanding both Greek in The Time Monster (1972) and Welsh in The Green Death. Although having failed to notice that Magister is Latin for Master, she probably deduced that Thescales was Greek for Master through simple logic and deduction. Whilst her nack for pronouncing Llanfairfach is achievable for anyone. So on the whole her knowledge of the Greek and Welsh language don’t really provide any more clues in establishing events in Jo’s timeline. Let’s return to her marriage to Professor Clifford Jones.

So it’s safe to assume that Jo was of legal age to marry Professor Jones at the end of The Green Death. This may seem a little obvious to point out, but it’s valid all the same. So if The Eleventh Doctor was referring to The Green Death when he last saw Jo, she was in her early twenties when she got married. It is also safe to presume that Jo was not a teenager since it would be somewhat ‘scandalous’ for a Nobel prize winning, world renowned biologist to marry a teenager when he himself clearly has a Doctoral degree. So Jo marries Professor Jones at 21 or 22 and her birth year is 1951, this means that Jo left UNIT in 1972/73. So when did she join UNIT?

When Jo first arrives at UNIT, The Brigadier tells The Third Doctor, ‘What you need, Doctor, as Miss Shaw herself so often remarked, is someone to pass you your test tubes and to tell you how brilliant you are. Miss Grant will fulfil that function admirably’ to which The Third Doctor says ‘Well, what's the girl doing here anyway? UNIT's no place for trainees’, to which The Brigadier replies ‘No, I couldn't agree more, Doctor, but Miss Grant was very keen to join us and she happens to have relatives in high places.’ Now apart from the little bit of nepotism going on here, the important words are ‘girl’ and ‘trainees’. Trainees are usually quiet young people looking to start their careers, people exploring possible career paths etc., and Jo is remarkably young, and The Third Doctor does show some scepticism towards someone her age being at UNIT. So what does that tell us? Well first, Jo is a little bit younger compared to Liz, and second, Jo has probably just left school. Again throughout her time with The Doctor, her education and qualifications are often referred to, as though they have just recently happened. Jo gladly announces that she studied General Science as if she just sat the exam. If Jo was born in 1951, she would have left school at 17/18, which means her arrival takes place in roughly 1968/69. However if the timeline, and Liz’s arrival at UNIT are correct, Jo joined UNIT after Liz’s departure which can’t be before 1969ish for reasons given previously. So let’s push things forward a bit to 1970/1971 with Jo joining UNIT at 19/20. This seem like a much better estimate, Jo is no longer a teenager, but a young adult; too young in The Doctor’s eyes, but a perfect fit to pass The Doctor test tubes and tell him how brilliant he is.

So on the whole let’s estimate Jo’s arrival at UNIT as taking place in 1970/71, and her departure as 1972/1973 (exactly when we’ll get to later). So on the basis of this Liz’s time with UNIT probably spanned a period between 1969-1970, the exact length doesn’t really matter. For now let’s turn to the third and final companion, Sarah Jane Smith.

Sarah Jane Smith was introduced in The Time Warrior (1973-74) and departed in The Hand of Fear (1976). Now Sarah Jane was born in 1951 according to The Sarah Jane Adventures two-parter The Temptation of Sarah Jane Smith (2008) where we see Sarah Jane at just a few months old. So it’s a matter of fact that Sarah Jane was indeed born in 1951. But this is where things gets interesting…..

During Invasion of the Dinosaurs (1974), Sarah Jane says that she is 23 years old. So if she was born in 1951, 23 years of age would put the events of Invasion of the Dinosaurs taking place in 1974 or 75. But this is where things get even more interesting.

During Pyramids of Mars (1975), Sarah Jane claims that she is from 1980s, and tells The Fourth Doctor that they know Sutekh (Gabriel Woolf) didn’t destroy the Earth in 1911, because Sarah Jane comes from the 1980s, so theoretically she is living proof. However in what is one of the most famous scenes, Sarah Jane looks out at a barren torn landscape, and realises the importance of stopping the Osirian Sutekh from succeeding in destroying the Earth. The scene itself is one of the best in the show’s history, but it doesn’t add up. We know of course when Pyramids of Mars was first broa