Director Ari Aster instantly made a name for himself upon the release of his debut feature, Hereditaryin 2018. The film premiered at the Sundance Film Festival, and the subsequent buzz made it one of the year's most anticipated releases. It opened in June of 2018 to rave reviews and is considered one of the best modern horror films.

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While Hereditary is no doubt a top-tier horror film, the 21st century has ushered in a great era for the genre, boasting many other worthy titles, as well. Here are five reasons Hereditary is the best 21st-century horror film, and five alternatives for whom a strong case can also be made.

Hereditary Is The Best: It Defies Expectations

The premise of Hereditary is that, after the death of a matriarch, her family inherits a sinister fate as the sacrificial lambs in a demonic cult. The film's trailer shows a funeral scene, which leads the audience to believe is the funeral of the matriarch.

As it turns out, though, the trailer's funeral scene is actually the burial of Charlie, the family's troubled child who is decapitated towards the beginning of the film, despite being advertised in trailers and on posters as one of the main characters. This establishes early on the sense that all bets are off and that the audience's expectations can be tossed out the window.

Alternative: Get Out

Daniel Kaluuya, as Chris Washington, looks forward in horror in Get Out

Comic actor and writer Jordan Peele shocked moviegoers with his horror directing chops in 2017's Get OutIt works as both a horror film with elements of comedy and an incisive political commentary. Like Hereditary, Get Out quickly upends audience expectations by presenting itself as a boilerplate socially conscious horror film, only to upend any and all audience expectations in a way that's thrilling and endlessly clever.

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Peele won an Oscar for his screenplay, and the film was a massive hit, grossing over $250 million worldwide—quite the haul, especially considering its meager $4.5 million budget.

Hereditary Is The Best: It's A Drama

One mark of a great horror film is that it can stand on its own without the actual horror elements. Hereditary is a perfect example of this dynamic in that, for all the scares it offers, it could be just as effective without any supernatural elements or typical horror elements.

Ari Aster says that, when pitching the project to studios, he didn't even try and sell it as a horror film, but rather a dark family drama that "descends into a nightmare," as he puts it. The scene writing is so good, the dialogue and performances so convincing, that Hereditary plays like real life, even when the subject matter turns fantastical.

Alternative: The Witch

Perhaps more of a gothic folktale than a full-on horror film, The Witch is the story of an early American family who abandons their town for reasons of religious purity and establishes a homestead in the New England woods. When their baby mysteriously vanishes, they blame its disappearance on a witch they believe lurks in the woods.

Like Get Out and Hereditary, The Witch is a highly impressive directorial debut. Filmmaker Robert Eggers is set to reunite with The Witch's Anya Taylor-Joy for his third film, The Northman, a Viking tale set a thousand years in the past.

Hereditary Is The Best: Toni Collette's Performance

Annie looking terrified in Hereditary

Horror films don't tend to garner much in the way of Oscar consideration, but Toni Collette not being nominated for her performance in Hereditary is as blasphemous as the plot of the movie itself. As Annie, Collette embodies the fear, anger, and trauma that consumes her character from beginning to end. Her reaction shots alone are terrifying, perhaps even more so than whatever she's reacting to.

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The key to Hereditary's success is the believability of it all. That begins with great writing, but, in this case, the script demanded a virtuosic lead performance by an actor up to the challenge. Toni Collette hits this one out of the park.

Alternative: Let The Right One In

Oskar holds knife in Let The Right One In

The 2008 Swedish film Let The Right One In is a bonafide classic. It's the story of a troubled boy who falls in love with a mysterious girl who is linked to a series of local murders.

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It's a vampire film that delivers on its promises of bloody horror, but it's equally compelling as a romance. Two years after its release, an American remake called Let Me In opened to positive reviews, as well; a rarity for horror remakes, and a testament to the strength of the source material.

Hereditary Is The Best: Possession Scenes

By the end of the film, the Graham family has been successfully sacrificed to Paimon, the "King of Hell." Annie's demonic antics in the film's finale sequence are truly horrifying, but equally, if not more disturbing, is the scene in the schoolroom where her son Peter is possessed. His body and face contorted, he slams his face into his desk, bloodying his nose to the horror of his teacher and classmates.

This scene is so powerful because it occurs at a moment when most horror movies afford the audience a respite: in the middle of the day, in a brightly lit public place. As mentioned earlier, though, Hereditary defies expectations at every opportunity. In this film, one of the scariest and most upsetting scenes occurs when the audience least expects it.

Alternative: The Babadook

Like Hereditary, 2014's The Babadook explores family dynamics in a terrifying fashion. It's the story of a single mother and her child whose relationship is strained by the manifestation of a creepy children's book that they make the mistake of reading together. At its core, the film is a metaphor for grief, which manifests itself violently at times, and the ending is as moving as it is disturbing.

Hereditary Is The Best: Realism, Surrealism, And Fantasy

Part of what makes Hereditary so unique is that it traffics in realism, surrealism, and fantasy. It's a convincing and compelling family drama, even without the horror elements thrown in. There's also terrifying genre elements, complete with blood and gore. Bridging the real and the fantastical, though, are the surrealistic dreamlike sequences that are as equally scary as the demonic possessions themselves.

The scene where Annie envisions her son's dead body being eaten by ants is both a viscerally horrifying and thematically resonant bit of foreshadowing, expressed through her subconsciousness.

Alternative: Saw

Cary Elwes reaching for the saw in Saw

In the early 2000s, mild PG-13 horror was en vogue. Films like The Ring, The Grudgeand The Others were doing well at the box office, and thus, kept getting churned out. Then, in 2004, along came Sawthe gritty, gory, micro-budget film about a kidnapped man whose only means of escape involves sawing off his own foot. Saw didn't just birth the "torture porn" sub-genre, it revitalized the horror genre as a whole, which had lost much of its teeth in the years preceding Saw's release.

In addition to the film's importance and influence, it boasts what is arguably the best horror twist ending this side of The Sixth SenseSaw was and still is a game-changer.

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