Empyrians are an avian (bird like) race of humanoids from the planet Empyria. Their spaceships closely resemble Earth flying saucers. The Empyrian who visited Earth did so using no disguise whatsoever, and it seems they dislike more than basic subterfuge being strongly moralistic creatures. Because the Empyrian chose to appear inside an amusement park, both he and his UFO passed unremarked as simply being part of the entertainment. This marks one of the very few times in the whole history of the Outer Limits that an alien, in its full natural form, goes undetected and unnoticed in contemporary human society.
The Empyrian possessed a cosmically powerful device in the form of an amulet, capable of matter manipulation.
Empyrians sought to recruit humans as a taskforce to work on diverting a planetoid that would impact first their homeworld Empyria and then lead to the further impact of Empyria into Earth - on a cosmic time scale, not in a few hours.