"They're all the same. Some stupid killer stalking some big-breasted girl who can't act who is always running up the stairs when she should be running out the front door." When Sidney Prescott (Neve Campbell) gave her famous critique of slasher movies in Wes Craven's "Scream," she summed up everything that had become so corny and predictable about the genre in the '80s. Of course, Craven's own Freddy Krueger was partially to blame, going from an inescapable monster haunting his victims' nightmares to a bogeyman with a penchant for novelty killings and gnarly one-liners. Hell, he even ended up rapping with the Fat Boys in the video for "Are You Ready For Freddy."

While there are many classic slasher movies out there, the genre often gets a bad rap for hackery and gimmickry, which, thanks to endless sequels, reboots, and remakes, is deserved to some extent. That is why it felt almost revelatory when I finally got around to watching "Black Christmas," one of the earliest examples. Bob Clark's disturbing wintry shocker isn't the first slasher ever made, but it is the movie credited with some of the most enduring tropes, from the Final Girl to the Killer POV, which John Carpenter deployed so brilliantly four years later with his game-changing "Halloween."

"Black Christmas" easily stands alongside the best of the genre. Like its fellow Canadian slashers "Prom Night" and "My Bloody Valentine," it has a harder edge than many of its Hollywood counterparts while displaying a much more human touch, infused with seasonal melancholy and an uncommon empathy for the victims. It also looks absolutely gorgeous, boasting an inky midwinter palette and the diffuse glow of Giallo-inflected fairy lights. Most importantly, it's pretty bloody scary, ending on a chilling note of ambiguity. But what do we know come that haunting final shot?

So What Happens In Black Christmas Again?

As the girls of a sorority house enjoy their Christmas party, we take the point of view of a heavy-breathing man as he prowls around outside before gaining access through the attic window. Downstairs, the phone rings, and Jess (Olivia Hussey) picks up. It is their regular obscene caller, "The Moaner," but tonight his shtick gets out of hand, provoking the brash and drunken Barb (Margot Kidder) to ridicule the creep. His tone turns very serious as he threatens to kill her before hanging up.

As the house mother Mrs. Mac (Marian Waldman), arrives bearing gifts, Clare (Lynne Griffin) heads upstairs to her room to pack for the holidays. The intruder is hiding in her closet and suffocates her with a plastic bag before dragging her corpse up to the attic, where he places her in a rocking chair by the window.

Nobody notices anything untoward until the next day when Clare's dad arrives to pick her up, but she doesn't meet him at the agreed time. Meanwhile, we meet Jess's insufferable boyfriend Peter (Keir Dullea), a concert pianist who is outraged when she tells him she is pregnant and plans to have an abortion. The cops initially fail to take Clare's disappearance seriously until later in the evening when a high school girl is also reported missing. Belatedly, a search is arranged, headed up by Lieutenant Fuller (John Saxon). Back at the house, Mrs. Mac discovers Clare's body in the attic and suffers a nasty fate.

The killings mount up and the obscene calls to the house grow more disturbing, prompting Fuller to arrange for a telephone engineer to tap the line. As the high school girl is found dead in the park and the police begin to suspect Peter, can Jess keep the murderer on the line long enough for them to trace the calls?

The Babysitter And The Man Upstairs

"Black Christmas" comes with a twist that probably won't surprise many people these days: The calls are eventually identified as coming from within the house. It's still a gut-lurching turn that would appear again in "When a Stranger Calls" a few years later, and it is commonly acknowledged as the first cinematic version of the Babysitter and the Man Upstairs urban legend.

The horrible tale gained notoriety in the '60s, and it goes like this. A babysitter is looking after two young kids one night when she receives a strange phone call from a man asking, "Have you checked the children?" She initially dismisses it, but the guy calls again a little while later and asks the same question. She knows she should go upstairs to make sure the kids are alright, but she's too terrified.

She calls the operator to see if it could be a friend playing tricks on her and the operator asks her to stay on the line while she traces the calls. When she comes back on, she sounds alarmed. "Get out of the house quickly! The police are on the way. The calls are coming from inside the house!"

Home is supposed to be where we feel safest and the story plays on the fear of someone violating that sanctuary. The legend is creepy enough, but it is also thought to be based on the real-life murder of 13-year-old babysitter Janett Christman in 1950 (via Psychology Today). She had managed to call the police station, but the operator was unable to make out what she was saying before the line went silent. When the police found her body, the phone receiver had been improperly placed back in its cradle (via Newspapers.com).

Peter Is Toxic But Not The Killer

"Black Christmas" doesn't do a terribly convincing job of casting suspicion on Jess's boyfriend, Peter. Keir Dullea ("2001: A Space Odyssey") makes him a toxic personality, but he is just too much of a loathsome a**hole from the outset, making him fall into the "too obvious" category of murder suspects.

The guy doesn't do himself any favors, though. He tries pressuring Jess into keeping the baby and giving up her dreams for the future, and his behavior becomes increasingly erratic when she refuses. First, we see him giving a wild piano recital before returning to violently smash the instrument, then he creeps up on Jess in the sorority house to accuse her of wanting to hurt their baby.

We later see him hanging around outside the house in the cold, and Jess begins to suspect he could be the killer when the caller uses the phrase "just like having a wart removed," which is how Peter earlier described the abortion procedure.

At the film's climax, Jess discovers the bodies of Barb and Phyl (Andrea Martin), another young woman living in the house, and flees the murderer into the basement. She hears him leave through the front door, which is when Peter suddenly appears at the window. He breaks in and approaches her while she cowers away, wielding a poker.

When the police arrive, they find Jess unconscious, cradling the bloodied body of Peter. Did she kill him herself, or did the murderer get to him? Either way, the cops decide he was responsible for the murders, setting up the finale. More likely he was still lurking near the house when he saw the real killer storming out and went to check on his girlfriend, paying the ultimate price for his horrible behavior towards her.

Who Is The Killer In Black Christmas?

One of the scariest aspects of "Black Christmas" is the series of phone calls the girls receive from the violent prowler. They're just obscene at first, but they take on a threatening tone after Barb insults the caller. After that, he becomes increasingly volatile as he howls, moans, jabbers, pleads, and appears to switch voices on the other end of the line. He barely says anything coherent beyond the first call, but some of his behavior may offer some insight into the killer's background.

At one point, he seems to relate a traumatic incident from the past, taking on the roles of both horrified mother and worried father: "Billy, what your mother and I must know is, where did you put the baby? Where did you put Agnes?"

Assuming the killer is Billy, we get further clues: We hear him singing the lullaby "Bye, Baby Bunting" and watch as he rocks Clare's corpse in the chair up in the attic, placing a doll in her lap. On a later call, he rants, "I know what you did, Billy. Filthy Billy," and soothes the sleeping Barb before he kills her in her bed. It seems to point toward Billy sexually assaulting a younger child and murdering her before she can say anything about it.

That's all we get, though, and it is easy to miss these details on the calls because Billy is ranting and raving so much. He sounds genuinely insane, and the most disturbing thing about the film is that we never learn his identity or find out his true back story. I much prefer this kind of approach to an unmasking of the killer, as it leaves us pondering the film's mysterious villain long after the credits have rolled.

The Final Girl And The Final Phone Call

Characters in slasher movies have a reputation for making unbelivably bad choices, and sadly the police in "Black Christmas" also fall into this category. There is a plus side, however, as their incompetence leaves us with one of the genre's most haunting conclusions.

After the cops find Jess in the basement with Peter, she is taken to her bedroom and sedated. Detective Fuller and his team head out for the night, stationing a cop at the front door. Yes, after the horrific evening she has just endured, they leave Jess alone next to the room where she earlier found two of her friends murdered.

Worse still, it soon becomes apparent that the police didn't bother to search the whole house. The camera slowly tracks to the attic hatch, where we become aware of footsteps and someone muttering on the other side before opening it. We see that Mrs. Mac and Clare are still up there with the girl still sitting in her rocking chair, staring lifelessly out of the attic window. The camera pulls back away to the outside of the house, and we hear the phone ringing.

If the first call of the film came after Billy killed the missing high school girl in the park, then he gets in touch with the house after every murder he commits. Now he is alone in the house with just Jess, who is heavily sedated in bed. Does that final phone call mean he has killed again and the Final Girl is his latest victim? We never find out, but it is a suitably bleak ending to this blackest of Christmases.

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