The piranhas of the air, shadow
Microscopic, swarming carnivores
“Silence in the Library/Forest of the Dead” and “Shadows of the Vashta Nerada”.
click on images to enlarge
As enemies go, the Vashta Nerada would probably be one of The Doctor’s most powerful enemies, as they are the only creatures he has ever fought in their natural state that he was convinced from the beginning he couldn’t defeat.
Essentially living shadows, the Vashta Nerada’s name means ‘the shadows that rend the flesh’, the creatures being microscopic beings that manifest as shadows to consume their prey, hatching from spores in trees. In most cases, the Vashta Nerada are relatively timid, with the species generally living on roadkill – although The Doctor implied that even on these planets They can be responsible for people going missing on walks in the woods or other areas at night , but some planets feature the Vashta Nerada actively hunting living prey.
The Doctor encountered the Vashta Nerada en masse for the first time when he visited the Library – an entire planet that had been turned into a massive library filled with every book in existence – in response to a call for help on the psychic paper (Later revealed to be from his future acquaintance River Song, River having accidentally sent the message to a younger version of The Doctor she knew rather than one who knew her). After meeting with River’s archaeological team, The Doctor learned that the entire Library had been mysteriously abandoned over a century ago, the last message being sent from it saying simply ‘4022 SAVED. NO SURVIVORS’, Donna Noble’s earlier search for other life forms having turned up over a million non-human life forms without any trace of humanoid life.
Although The Doctor quickly deduced the presence of the Vashta Nerada, it was too late for him to save Miss Evangelista, one of the expedition members, from being devoured by the Vashta Nerada while still in her space suit, a communication device she wore that was linked to her nervous system creating a ‘Data Ghost’ of her personality that could communicate with the others before it lost all power itself. As the ship’s pilot was consumed by the Vashta Nerada, The Doctor attempted to use the Library teleport system to send Donna back to the TARDIS, but the teleport was interrupted and Donna was apparently killed, The Doctor only just managing to escape being devoured by more shadows. However, thinking back on the message from the Library, The Doctor realised that the missing 4022 people had been literally saved from the Vashta Nerada; CAL – the Library’s controlling computer, simultaneously the mind of a terminally ill girl who had been preserved by the Library’s founders to give her some kind of life – had transmitted them into her databanks when the Vashta Nerada began their attack. Even worse, the Vashta Nerada were able to create bodies for themselves by animating the skeleton-filled suits of the deceased expedition members, later learning to communicate with The Doctor by using the ‘Data Ghost’ to teach them how to speak.
Having learned from the Vashta Nerada that they had come to the Library because their ‘eggs’ had been in the wood that was used to make the Library’s books, The Doctor was able to devise a means of boosting CAL’s brainpower enough to transfer the 4022 survivors – now including Donna – out of her databanks. Although The Doctor was willing to use himself as the connection to boost CAL’s processing power, River took that position herself, reasoning that The Doctor wouldn’t be able to survive the experience and knowing that he had to live through this confrontation so that he could meet her past self in his future. Although the Vashta Nerada briefly tried to attack The Doctor as he prepared CAL for transfer, The Doctor convinced them to withdraw simply by challenging them to access the Library’s databanks and look him up, the information They discovered prompting them to give The Doctor a day to evacuate everyone from the Library (And also transfer River’s ‘Data Ghost’ – saved in a device The Doctor had planted in a sonic screwdriver he would give her in the future – into CAL so that a part of River could live on).
The Doctor encountered the Vashta Nerada again in his eleventh incarnation when he and his companion Amy Pond visited the underwater city Poseidon Eight, one of many underwater colonies established after a great flood had left most of Earth’s land masses uninhabitable. Having been separated from the TARDIS when a giant shark-like creature shattered the tunnel leading back to the area where they had materialised, The Doctor and Amy advanced to the main building of the facility, where they were shocked to discover that not only were the city’s population infected by an unidentified virus, but the Vashta Nerada were active (The Doctor immediately noting that these had to be Vashta Nerada from another world as Earth’s ‘breed’ of Vashta Nerada were passive creatures that fed mainly on roadkill).
Using the base’s emergency light systems, The Doctor was able to illuminate various corridors long enough for him and Amy to reactivate Poseidon Eight’s main power generators, subsequently driving a couple of Vashta Nerada swarms out of the diving suits they were using as hosts by forcing them into an area where he could activate the emergency lighting at full strength to ‘force’ them out of the suits. Having identified the cause of the rift that drew the Vashta Nerada and the ‘shark’ to Earth as the 1940s American ship the USS Eldridge, The Doctor realised that Project Rainbow – a secret naval experiment to create an invisible ship in the Second World War – had created a temporal rift that had drawn the shark, the Vashta Nerada, and the virus into Poseidon Eight. After creating a cure for the virus, The Doctor and Amy were able to use the base’s service tunnels to return to the TARDIS and take a quick hop to the USS Eldridge, shutting down the rift-generating equipment and sending the shark and the Vashta Nerada back where they came from (Although Amy was forced to trick another pair of Vashta Nerada-inhabited suits into entering a bilge pump room so that she could expel them from the ship).