In the original movie Highlander, humans who are born immortal possess an energy within them that can be absorbed by another immortal if they kill the former. An immortal ages normally until experiencing a fatal incident. After this First Death, they no longer age. In the original film, the Egyptian warrior Ramírez demonstrates to protagonist Connor MacLeod that they are immortals and have a connection to nature. As he shows Connor that they can survive being struck by lightning, as well as sense the emotions and heartbeat of a nearby stag, he explains that this power and the sensations it brings "is the Quickening." The film also shows that the Quickening energy allows immortals to sense each other.