Monthly Monster: The Vashta Nerada

Monster File for the Vashta Nerada:

"Almost every species in the universe has an irrational fear of the dark, but they're wrong; because it's not irrational. It's the Vashta Nerada."
--The Tenth Doctor, Silence of the Library

The Vashta Nerada are microscopic beings that exist on practically every planet in the universe. Their name means 'Shadows that melt the flesh', and that is, when there are enough of them, exactly what they do.

A swarm of Vashta Nerada

The Vashta Nerada are born in trees as microscopic spores, living their lives in forests. The spores are very resilient, enough so that they can survive the processing of trees to books and paper. They would latch themselves to their prey as a second shadow, then take over, reducing their victim to bones.

For Shadows of the Vashta Nerada and Silence in the Library/Forest of the Dead

The Vashta Nerada in Poseidon 8

 A temporal rift in the 23rd Century resulted in a swarm of Vashta Nerada being transplanted to the underwater city Poseidon 8 on Earth. The Eleventh Doctor and Amy Pond were able to defeat the Vashta Nerada and returned the Vashta Nerada to their original planet. (Shadows of the Vashta Nerada)

The Vashta Nerada in The Library

In the 50th century, The Library was invaded by over a million million Vashta Nerada, transported to The Library as spores in the books. The planet was empty for one hundered years the Tenth Doctor, Donna Noble, and an archaeological expedition landed on the planet, the expedition to investigate the disappearance of the 4,022 people who were in The Library at the time of the attack. River Song sacrificed herself in order to return all the people, who had been 'saved' (Literally. Like an e-mail.). After the safe return of the 4,022 people, River Song was saved to the computer along with the others of the expedition. (Silence of the Library/Forest of the Dead)

Remember: Count the shadows. If you have two shadows, either there are two light fixtures behind you, or you're about to become the next victim of the Vashta Nerada.