Like a lurking shark below the ocean's surface, offscreen deaths in horror movies prove that it isn't always what's seen that's scary.

HBO has a ton of horror movies slated for September, gearing up for the upcoming Halloween season, but is sadly missing some of the bigger franchises of the genre. Some of these horror series, particularly slashers like Halloween and Friday The 13th, have quite a few characters die at the hands of a single antagonist. But this doesn't always happen on-screen. When done properly, the character will still serve some purpose in the narrative later on, even if just for a single scare.

These characters faced a fate that proved a movie doesn't require blood and guts to be scary and sometimes the audience doesn't even need to see what happened to feel the twinge of fear. But off-screen means completely off-screen, so legendary scenes like the opening of Jaws don't fit the bill.

Ridley Scott's classic sci-fi movie Alien was and remains a terrifying trendsetter. No number of sequels can dull the dark corridor-fueled impact of the original horrific masterpiece, which doesn't even need to go for blood and guts to get its scares across.

In a way, just about every human character's death in Alien (save for John Hurt's Kane) is blink-and-you'll-miss-it (Parker and Brett get the Xenomorph's smaller mouth to their heads). But it's telling that the film can make not one, but two, offscreen character deaths as terrifying and emotionally devastating as a baby alien bursting from the chest of a man enjoying breakfast cereal. The first of the two (but the third of sixth character deaths overall) is Tom Skerritt's tunnel-crawling captain of the Nostromo.

Over 40 years later, the original is still the best film in the Alien and Predator universe, and Scott's 1979 Alien is arguably one of the very few perfect films. There are no superfluous scenes, no scenes cut too short, and no moment that lands with a thud instead of a gasp.

But the film's scariest death isn't even Kane's via the iconic chest-bursting, it's Lambert's. Lambert is the final crew member of the Nostromo to perish, and she does it off-screen, but her screams tell a horrid story. It's not quite clear if the Alien sexually violates Ms. Lambert, but the shot just before her scream is of the Xenomorph's tail sliding on the ground between her legs. It's left to the audience's imagination, and the vocal work done by Veronica Cartwright is top-notch.

One of the definitive summer camp movies of the 1980s or any other decade, Friday the 13th has only gotten better over time. The film has a straightforward, blunt impact and decidedly non-cinematic visual style that makes it feel less like a movie and more like a journey to one deadly night in an otherwise innocuous camp.

It also has a terrific build-up in terms of intensity. Ned is the first of the main counselors to actually meet Pamela Voorhees on Camp Crystal Lake grounds, and his death is entirely off-screen. Jack and Marcie are getting intimate, and a sad Ned puts his hands in his pockets, whistles, and wanders around Camp Crystal Lake. He sees a figure in a yellow raincoat standing on one of the cabins' decks (in a bit of the movie's most gloomily effective imagery) and approaches in a friendly manner. The next time the viewer sees the likable character, he has his throat slit and is on the top bunk, with Jack and Marcie below. Below them, Mrs. Voorhees.

Friday the 13th may be tame by today's standards, but at the time, its elaborate death scenes and maternally-based twist ending were a shock. It also has some superb jump scares, such as when Alice looks around for Bill, who has gone to work on the generators.

Once Alice reaches the shed where Bill should be working, she finds it empty with the door wide open. After deciding to move on and search elsewhere, she closes the door, only to find Bill. Like the remainder of the characters in the original Friday the 13th, Bill was a sweet-natured character, and seeing him with arrows in his groin, throat, and eye is jarring.

Before David Gordon Green's Halloween (2018) retconned its twist (and the movie as a whole), Halloween II contained one of the most controversial mic drops in the history of the franchise. Having Laurie Strode secretly be Michael Myers' little sister gives a terrifying phantom quite too much human motivation, but for the most part, Halloween II comes the closest to capturing the tone and overall magic of John Carpenter's original film. That said, Green's trilogy (set to conclude in October with Halloween Ends) has done remarkably well on that front considering four decades have transpired.

It is, however, significantly more violent. Even the several off-screen character deaths are revealed with imagery more reminiscent of Friday the 13th than Halloween. The most memorable of the bunch is Dr. Mixter's, when his body is discovered with a needle in his eye.

Of the first four Friday the 13th films, Part III is the weakest, but it's not without its gimmicky charms. With the right set-up, the 3-D version of the film can look phenomenal, but even with the old-fashioned glasses, the barn-set scenes are a lot of fun.

Bikers Fox, Ali, and Loco — who had their modes of transport backed into — are planning revenge in the form of gasoline theft. The female member of the trio, Fox, notices the film's established makeshift rope swing that hangs from the barn's second-floor ceiling. In the best use of tension-building until the prolonged third-act chase, Fox swings in and out of view of the audience (and Loco) with glee. Until she doesn't.

Before Philip Seymour Hoffman played the character in Red Dragon, Avatar's Stephen Lang took on the role of doomed journalist Freddy Lounds in Michael Mann's Manhunter, the first adaptation of a Hannibal Lecter novel.

Lounds' torture is where the line "Do you see?" comes from. And it's in that literally torturous buildup that the final result (Lounds on fire in a wheelchair) becomes just that much more effective. The audience doesn't need to see "The Red Dragon" do his work for them to know exactly what he's doing, the flaming body just shows them the method of execution.

Predator is filled with tough characters, but tracker Billy seemed a cut above. However, his final scream is absolutely horrifying.

In an effort he obviously knows will be fatal, Billy nods off Dutch and the remainder of the film's survivors. He stands on a log, knife in hand, and waits for the fight. Judging by how long it takes for the audience to hear Billy's scream, it stands to reason the clash was fairly one-sided.

The death of Randy, one of Scream 2's most likable characters, hits hard. His personality was embraced lovingly by fans immediately, to the point that his presence hasn't left the franchise, even in its most recent installment.

Debbie Salt aka Nancy Loomis aka Billy's mother gloats about her slaying of the fan favorite, and in fact, it's most likely Randy was the only person she killed throughout the entire film. The viewer doesn't need to see Randy actually get stabbed to feel awful for him, as the film manages to make a shaking van horrific imagery all its own.

The overall impact of The Blair Witch Project has dwindled a bit over the years, but when it was released, it captured the pop culture zeitgeist by storm. Whether the events seen had transpired or not, audiences were left with their jaws dropped. Early in the film, the legend is explained to the three protagonists, Heather, Mike, and Josh. They're told of a kidnapper/murderer who brought his victims down to his basement in pairs, forcing one to stand in the corner as he attacked the other.

The film's ending is both terrifying and an excellent example of successfully following through on foreshadowing. Heather and Mike search for the now-disappeared Josh. They don't find him, but Mike finds someone off camera. Heather rushes down to the basement where she finds Mike standing unresponsive in the corner. His assumed death is scary enough, but then something comes straight for Heather.

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Ben Hathaway is a novelist, copywriter, and film buff located in Richmond, VA. While he loves cinema as a whole, his favored genre is horror.