The Davannans are a humanoid species with white pupil-less eyes and a culture which seems to reject emotions. They also have telepathic capabilities to some extent and, by staring at humans with their blank eyes are capable of anything: from hypnotic suggestion to killing by destructing the optic and nervous tissues of the victim.
For nourishment, they consume a type of black liquid containing all necessary vitamins and other nutrients. The Devannans have a weakness concerning their extremely sensitive hearing, with loud noises having a painful effect on them.
As of the 20th century, this species had suffered a devastating nuclear war and was dying out from an epidemic disease which causes their blood to "evaporate". A Davannan agent was sent to Earth to study the effects of Human blood in their own biology, but after the alien died in a car accident, the planned invasion might have been called off.
- Not of this Earth (1957)
- They are never referred to as "Davannans", the name is instead inferred from their homeworld which is named Davanna.
- The nature of the small, hovering alien creature which kills a man in the movie is left unexplained, but may represent a non-sapient species from Davanna's native fauna.