The Selyoids were beings of pure light.
Selyoids were originally beings of light, but climate change caused their scientists to devise a corporeal form. Their corporeal form was a primordial soup capable of travelling through space on an asteroid.
On their own planet, the Selyoids lived purely to express their creativity, as a race of artists. Their scientists were outcasts.
The Selyoids once invaded Los Angeles and somehow changed movies, including The Time Machine. The Second Doctor, Ben and Polly stopped them. (PROSE: Dying in the Sun, Synthespians™)
Behind the scenes
- The name of the Selyoid obviously derives from celluloid, a chemical made in the production of film stock.