Immortal (Highlander)

According to the original version of the controversial 1991 film Highlander II: The Quickening, the Immortals are a race of humanoids from the planet Zeist. The name "Immortal" might not be the true name of the species, but it is the name that they are most associated with.

Biology
The physiology of the Immortals is somewhat odd, as on their home planet they are not truly immortal. They are only immortal whilst they are on the planet Earth, during which time they can only be killed by severing the head from their body and "The Quickening" takes place. If the Quickening does not take place, then the immortal will come back.

Also, they are only immortal when there is more than one Immortal occupying the planet - when one Immortal kills another on Earth, all the strength, memories and attributes of the deceased are passed on to the victor; this phenomenon is called "the Quickening". When there is only one Immortal left on Earth they become mortal once again until another Immortal from Zeist arrives on the planet.

Culture and society
The Immortals seem to have some knowledge of Earth culture, and for unknown reasons are forbidden from fighting on holy ground.

Appearances

 * Highlander (1986)
 * Highlander II: The Quickening (1991)
 * Highlander III: The Sorcerer (1994)
 * Highlander: Endgame (2000)
 * Highlander: The Source (2007)

Trivia
It is only in the original version of Highlander II: The Quickening where Immortals are said to be aliens. Due to the fandom condemning the movie, an amended version was released, in which the Immortals are said to be humans coming from a technologically advanced civilisation far back in Earth's past, before recorded history.