Billy (Original timeline)

Billy (real name unknown)
Known aliases:	The Sorority House Killer The Moaner
Birth:	c. 1939-unknown
Death:	Unknown
Appearance:	Black Christmas (1974)

Billy is the psychopathic killer and the antagonist in the 1974 original film Black Christmas. His identity is never seen or revealed, save for his eye.

History

Very little is known about Billy, even his appearance as he is usually seen off screen or in the shadow and the only body parts shown are he blue jeans, his eye, and his hands. All that is known is that he's clearly mentally deranged and enjoyed tormenting his victims. He was simply known to the sorority girls as the "Moaner". He had been making very obscene/perverted phone calls. He apparently decides to start killing when one of the girls, provokes him.

Due to Billy's clear deranged state, not much is completely known. Even from what he says to the girls, its not known if his back story is real or just part of his deluded mind. But never the less, he hints through his phone calls, that he had a baby sister named Agnes and two parents. For some unknown reason, he called all his female victims "Agnes"

Its hinted his parents sensed he was disturbed as his "father" yelled at his mother for leaving Agnes alone with Billy. Its believed he killed/or physically maimed his baby sister Agnes; for unknown reasons. However, Agnes apparently committed some unknown "bad" deed with Billy.

During the confrontation with the sorority girls, whom he calls Agnes, he says "don't tell them what we did". Billy is never really caught at the end of the film. After he comes close to killing Jess Bradford, she's left shaken and paranoid to her fears. To the point that she quickly believes that her boyfriend, Peter Smythe was the killer. She wastes no time and kills her him while in a state of panic.

The police quickly assume it was Peter and don't bother to check the attic. However, as they leave a sedated Jesse alone in the sorority house. And Billy's voice is heard once again and revealed he's upstairs in the attic. The phone rings; indicating he will soon finish the job with Jesse. Billy is still at large.

Trivia

• After seeing the ending of the film, studio executives asked director Bob Clark to change the ending. The proposed idea was to have the cops leaving Jess alone with Chris, Claire's boyfriend. She wakes up and he says, "Agnes, don't tell them what we did." Then he kills her. However, Clark refused and insisted that the ending be ambiguous.
• Though its never stated, it is possibly Billy had committed crimes before he entered the sorority house. As Claire stated in the film earlier, that a local town girl had been raped. Though its unknown if it was Billy since his crimes were more towards violent murders.