Once more stepping aside from a four-story arc structure to tell more standalone tales, UNIT looks to the past and the secrets within the Black Archive as three new threats emerge in the aptly-titled Revisitations.

Chris Chapman opens this seventh series with a two-part serial entitled ‘Hosts of the Wirrn,’ continuing this series’s strong effort to blend the classic and modern stylings of Doctor Who to great effect. Since their introduction in ‘The Ark in Space,’ the insectoid Wirrn with larvae that eat the host from the inside out and that contain all of the race memories have been one of the most formidable creatures the Doctor has ever come across. Able to exist in outer space and withstand all manners of attack, the dangerous potential these creatures possess even as they simply try to survive is wholly unique and has led to some of the most gruesome horror the franchise has produced in any medium. Accordingly, the Wirrn are also the perfect threat for the modern version of UNIT and the unassuming world at large to confront, and the organisation’s underlying blend of compassion, reason, and might under the guidance of Kate Stewart has never been tested quite so bluntly as when taking control of a lone gift left by the Master has unexpected repercussions.

The first part of this tale is remarkably adept at bringing newcomers and seasoned fans alike up to speed with the furtive organisation working beneath the Tower of London, exploiting the unique interview process and the first day on the job of entomologist Shana Siddiqui to highlight the technological marvels UNIT possesses and the measures it employs to keep its existence a secret and its staff and interiors free of external contamination. Vineeta Rishi and Ingrid Oliver form a remarkable chemistry incredibly quickly as Shana and Osgood as two outsiders find a common bond despite Osgood’s inherent dislike of insects, and the transformations that begin to occur among the UNIT staff as containment is unknowingly breached make for a fascinatingly tense atmosphere that the Wirrn’s altering of familiar voices complements perfectly. With all of UNIT’s secrets now belonging to this foe as the Queen so lovingly nicknamed Elizabeth continues to spread her influence, the scene is aptly set for a momentous second half.

As part two begins, the Wirrn spread is told over two very distinct storylines, one as its infuence becomes public and the other as Shana finds herself fighting to retain her sense of identity after exposure to just a microscopic amount of alien material. Indeed, it’s here that Rishi truly shines as Shana fights with every fibre of her being to stop the Wirrn spread from overtaking her even as she hears the voices of the swarm beckoning to her. As she slowly succumbs to the increasing pressure within while trying to stay true to her own morals and providing what information she can to UNIT and the people who have finally given her a sense of belonging, the very personal and emotional turmoil of this transformative process adds a magnificent extra layer of depth to proceedings that allows it to resonate all the more profoundly when added to the fates of those who have already fallen victim.

Naturally, Kate Stewart takes the loss of so many lives both within and outside of UNIT personally, blaming herself for each and every one because of her own decisions regarding the material in her charge. Jemma Redgrave has always done well with adding an air of empathy to her command that necessarily entails tough decisions and sacrifices, and she excels by exuding an understated power throughout but particularly when negotiating with the Queen who dwarfs everything around her. As the pasts of both this particular Wirrn and of UNIT collide to provide a reason for this distinctive outbreak as well as a solution, respectively, a nice sense of cohesiveness is afforded ‘Hosts of the Wirrn,’ and it’s clear that these events will have a lasting impact on those who have survived that will go far beyond a simple cover story steeped in elements of the truth. While it will remain to be seen just how Shana is integrated into future events- if at all- given her ultimate fate here, the only potential shortcoming of this story is that it does rely on a newcomer to make the vital sacrifice, giving a nice sense of closure to Shana’s story about acceptance but also taking away from some of the potential impact of a more established figure doing the same.

In ‘Breach of Trust’ by David K Barnes, an alien vessel arrives on Earth with its two occupants seeking refuge. Speaking via the harmonics of music, UNIT is able to develop a translator that allows communication, and this imperiled mother and daughter warn of an oncoming fleet of thousands of Kalvyri warships poised to destroy the Earth as their leader looks to further refine the destructive capabilities of their voices. The seemingly good intentions are called squarely into question, however, when an old UNIT report from Mike Yates warns of a previous encounter in which humans were surreptitiously fooled by the Kalvyri, especially when a Kalvyri-specific sound weapon that is fueled by a hatred for foes and focused by the user’s love for those needing protection is brought up from the Black Archive to potentially be used against the oncoming invaders.

Yet as the insistence for destruction of Jarrack’s fleet that is much smaller than warned continues to escalate, it’s clear that there is another element to this story that has not been revealed, and the truth sets all of UNIT on a path filled with ethical and practical implications. Again, Jemma Redgrave excels as Kate Stewart must balance the potential destruction of Earth that has unwittingly been brought into an alien affair with the fates of these two Kalvyri whom Jarrack admits he will execute for not falling in line with his decrees. Facing what appears to be a far superior force, UNIT must decide whether to fight back or acquiesce, and the very personal plight of a mother and daughter facing death lends a very intimate aspect to this decision that brings out impassioned pleas from Kate, Osgood, and Carter alike with a genuine emotion not often seen from these seasoned veterans. With Jarrack remaining out of reach for the entirety of the story, this threat never truly has the chance to manifest on a palpable level, but the dissent sown within UNIT’s ranks as opinions and scruples collide makes for a unique and dramatically satisfying tale that uses a very small scale to develop its much grander ambitions.

Closing out UNIT: Revisitations is Roy Gill’s ‘Open the Box’ in which Kate Stewart leads her team to study the goings-on and merit of an international organisation devoted to meditation and mental fortitude to make fears anything but. Unsurprisingly, the force behind this practice is not quite as benign as expected, and the surprising reappearance of Captain Chin Lee following her involvement with the Master’s affairs at Stangmoor Prison in ‘The Mind of Evil’ so long ago again provides UNIT with yet another opportunity to reflect on its past. Though Kate would like to believe that her organisation has moved beyond its days of explosively dealing with issues, she must confront the validity of more aggressive means of action as the hidden truth dating back to Stangmoor continues to swell and break free, and Chin Lee herself forces Kate to wonder just what harm UNIT might be doing to individuals when they are left alone to determine their place and path in life after one of their operations. To this effect, Pik-Sin Lim manages to imbue an intriguing blend of optimism and torment to her performance that excellently hints at just what she has been through and the misguided beliefs that still fuel her to this day.

Given the dialogue, it was almost inevitable that the character of Seth should be somewhat over the top as he yearns to feed his increasing hunger, but this fortunately does not detract from the glimpses of the leads’ internal fears and the ramifications of making deep fears manifest so overtly as the world literally changes around individuals. One hour isn’t quite enough time to fully pay homage to its foundational story while also fully developing its own story in full detail, but ‘Open the Box’ is nonetheless an enjoyable listen that portrays its core characters in a slightly different light than usual while still highlighting what makes them so strong and unique no matter the situation or state of mind.

Wisely avoiding telling three or four direct sequels to earlier tales, UNIT: Revisitations proves the inherent variety of this audio franchise even with all of the stories following the remit of looking to the past to develop the present. Although this naturally means that some creativity has to be curtailed to mesh with what has come before, this is another wonderful set that again proves how well the different eras of Doctor Who can blend without simply treading familiar ground over and over again.