The Living Receiver
Donnie Darko
Played by Jake Gyllenhaal
A troubled sixteen-year-old in Middlesex, Virginia, who sleepwalks out of his bedroom minutes before a jet engine falls into it - and is chosen as the Living Receiver of the Tangent Universe that follows.

Donnie is in therapy, on (placebo) medication, and has a history of arson. His psychiatrist calls his visions paranoid schizophrenia; Sparrow's book calls them the torment of the Living Receiver. The film never forces a choice.
Over 28 days Donnie floods his school, burns Jim Cunningham's house, falls in love with Gretchen Ross, discovers Roberta Sparrow's book, and finally - after Gretchen is killed and he shoots Frank - drives to Carpathian Ridge and uses his Fourth Dimensional Power to tear the engine from the plane carrying his mother and sister and send it back through the Vortex to October 2.
The Tangent Universe collapses and the Primary Universe resumes. Donnie wakes in his bed on the night of October 2, laughs, and stays there as the engine falls. Nothing in Sparrow's text requires the Living Receiver to die once the Artifact is returned; why Donnie does is discussed on the ending page.
What happens to this character.