"The Ark in Space" is also an early and prominent example of producer Philip Hinchcliffe's new template for the long-lived series, one that involved a dramatic shift towards more overt horror territory.
In these tales, the universe itself seemed to take on a new, distinctly mysterious and dark aura. There was a strong Lovecraftian angle to the series at this juncture, as monstrous gods (Sutekh), species (The Fendahl), and personalities (Morbius) threatened to arise from centuries-long slumber, or even from entrapment in the ice (Krynoid) to threaten mankind and the universe at large.
"The Ark in Space" expertly sets that terrifying tone for this new concentration on horror, and does so from the inaugural shot; a point-of-view perspective shot that reveals some kind of green-slime-covered monster attacking a sleeping human inside a suspended-animation chamber.
Now, the "entire human race" awaits "a trumpet blast," to wake up, start over again, and re-populate the healed planet.
"What an inventive, invincible species! It's only been a few million years since they crawled up out of the mud and learned to walk. Puny, defenseless bipeds. They've survived flood, famine and plague. They've survived cosmic wars and holocausts. And now, here they are, out among the stars, waiting to begin a new life. Ready to out-sit eternity. They're indomitable. Indomitable."
The Wirrn swarm once lived in the Andromeda Galaxy but their "Old Lands" were seized by space faring human beings, and the giant bugs have been looking for a new home ever since. Not to mention revenge. Again, consider how the discussion of "Old Lands" and the resurrection/return of an ancient evil resonates with the Lovecraft template.
The Wirrn plan to utilize the sleeping human race on Nerva as their primary food source, and more. When they digest life forms, the Wirrn also absorb the knowledge of all such life, and so plan to become a "technological species" within one generation.
As his wont, the Doctor has once more stumbled into an inter-species battle for survival, and must pick a side for which to fight. Given his history, and the affirmative quotation regarding mankind above, it's not too difficult to guess where his loyalties fall.
But one delightful element of "The Ark in Space" is that it isn't simply a serial about man vs. alien, or the Doctor racing to the rescue; much like the proverbial Time Traveler negotiating the breach between the Eloi and the Morlock.
But beyond their specialties, these examples of future man are lost; diffident and vulnerable.
In real life, the debate was whether or not workers would be more productive simply doing one task, or multi-tasking. In the Recession of the early-to-mid 1990s, the trend towards specialization largely faded out and multi-tasking -- the performance of multiple tasks by one person -- carried the day. With layoffs and an epidemic of "down-sizing" (a new term in the 1990s) workers had to prove their flexibility and worth to companies looking to cut and slash.
"The Ark in Space" debates this issue, in the process considering every shade of each argument. Vira is designated a physician, but when Noah, the team leader, is absorbed by the Wirrn, she must step up to the plate and take command. It is not her nature, and it's not her "job description," but fate has made these arrangements for her. She will either grow...or fail. And if she fails, the human race fails.
They need only to...consume talented individuals to grow and fatten and prosper. Because they are an insect culture, the Wirrn are also a hive mind. And another word for that, of course, is "corporate entity."
So make any comparisons you wish there, between business executives and parasitic insects. They are the "users" of the workers, who end up on top by "absorbing" the talents of those they exploit.
The more closely one studies "The Ark in Space," the more fully this debate about specialization in the human animal bubbles through to the surface.
In Part Four of the serial, for instance, Sarah Jane Smith -- a reporter by trade -- leaves her comfort zone behind in more ways than one by transporting an electronic cable through an egregiously tight vent shaft.
Like Vira, who becomes a sturdy and dependable commanding officer, Sarah adapts to the needs of the environment instead of sticking to one particular skill set. Rather than specialize herself into oblivion, she grows and changes. Again, this is gazed upon as an extemely valuable trait.
An engineer named Rogan ultimately saves the day by releasing the docking clamps on a space shuttle containing the Wirrn. Before he does so, Rogan tellingly informs the Doctor "This is my job," with the emphasis on the descriptor "my." He meets his destiny by fulfilling the task he was trained to do. He considers that task an oath, as we can see from his self-sacrifice.
Similarly, Noah retains enough of his humanity to also fulfill his training...as a leader. In this case, he saves the humans by deceiving the Wirrn into space; to the outside hull of the station.
Uniquely, Noah has not only fulfilled his compact with the humans, he has also, in a very strange way "led" the Wirrn as well. Right off a cliff, so-to-speak. It's illuminating to consider that the humans and the Wirrns are both, at times in this four-part serial, led by one man: Noah. This means, I suppose that once a leader, always a leader, regardless of the species one commands. Once more, the idea being explored in "The Ark in Space" is training or career preparation as nothing less than destiny.
The Wirrn continue to live by their biological life cycle (eat, absorb, lay eggs, then start again) and in the end that's simply not enough to make them the dominant species. Possessed of a corporate mentality, they cannot, apparently, resist from following Noah (their metaphorical CEO, I suppose...), into disaster. There must be learning and adaptation for survival, this serial implies.
In terms of context, "The Ark in Space" is also fascinating because it reveals Dr. Who, along with Space:1999 (also premiering in 1975) at the spearhead of the movement to re-define space adventuring in darker, more grotesque terms than in previous TV efforts.
In the late 1960s, Star Trek had beautifully and colorfully presented the idea of the United Nations in Space, with Cold War enemies such as the Klingons and the Federation, and each unaligned planet representing an island across a cosmic ocean, to either join the Federation, or team up with the enemy. By the late 1970s, the paradigm shifted. Space, in 1999 and the Hinchcliffe years of Who, no longer existed simply as an extended metaphor for East/West relations here on Earth.
And at the end of the decade, of course, Ridley Scott's brilliant film Alien (1979) took the concept of outer space horror about as far as it could possibly go, with the riveting, gorgeously visualized tale of a "perfect" (and perfectly hostile) alien parasite.
Today, one scene in "Ark in Space" forecasts Alien especially closely. Sarah Jane goes into that tight vent shaft, wearing a head-set "two-way radio," while in another chamber crewmen monitor her progress going from "juncture" to "juncture."
At one point, Sarah encounters the Wirrn, but they are (safely) on the other side of a vent grille. In Alien, of course, Captain Dallas goes into the Nostromo's air duct, also wearing such a head set, and is monitored closely by Lambert and Parker, moving from "junction" to "junction." He comes to a much unhappier end, than Sarah-Jane.
The point of this comparison is not to declare in any way, shape or form that Alien ripped off this TV show or that TV show, only that there was clearly something in the water in the 1970s, so-to-speak, moving space adventure in the direction of more dark, paranoid, chaotic imaginings.
Perhaps it was the Energy Crisis that made all the difference: a global race for resources during a period of scarcity and market manipulation. In many of these dramas, from "The Ark in Space" to "Dragon's Domain" to Alien, it is man himself who becomes the ultimate resource for otherworldly beings; to be used up, and rather maliciously so.
"The Ark in Space" sets the dark, ominous tone for much of Tom Baker's early tenure on Doctor Who, and so there's a chilling, unsettling atmosphere to the entire enterprise. In this story, man is dislodged from his home on Earth and sleeping in the ultimate "dark" -- outer space itself. And worse, there really are hungry monsters under the bed, just waiting to get him.
"The Ark in Space" exploits this universal fear well, despite a not-very convincing Wirrn monster costume, and succeeds in being suspenseful largely because it is well-written and well-performed. The Doctor goes on at length about the idea of being "digested" and "absorbed" by the Wirrn, and his colorful descriptions are more than enough to give those with a strong imagination a lingering case of the creeps.
By 1975, Doctor Who had been around for more than a decade.