The Voilax are a species of aliens in Estrangeria. They are controlled by Jeff Anderson, the prime
  minister of Great Britain, who has them under a trance using his Implant Machine.
The Voilax were originally a species famed for warfare, most notably against the Sontarans, the Kulty'n and Guarnd. This was because the Implant Machine could control the species, meaning that they were not troubled by emotions or anything else that might cause them to retreat.
One mothership crashed into the Earth in the mid-20th century. Some of the Voilax in it escaped, as did Jeff Anderson, also involved in the crash.
The Voilax do not have free will, rather they obey their master. Thomas Stillton hopes that when he releases the human race from their trance, he will be able to do the same for the Voilax, to allow them to make the choice as to whether they are peaceful.