5 Times an exorcism in a horror movie didn’t go as expected

Exorcisms have been a horror movie mainstay for years, providing a chilling conflict between good and evil that usually culminates in the triumph of faith over evil. But what if those spiritual clashes don't quite work out as planned? When the sacred prayers fail, the ceremonies go awry, or worse, the evil adapts? That's when the terror becomes indelible.

In most horror movies, exorcisms are the be-all and end-all, a dramatic confrontation in which priests remain resolute and demons are cast out. But the genre has become braver and more volatile in recent decades, often turning expectations upside down. Some of the most frightening scenes in horror history are the result of exorcisms that went catastrophically wrong or created outcomes beyond anyone's wildest dreams.

Whether it's an exorcism that results in sudden death, a possession that merely changes victims, or a summoning in the guise of salvation, these instances serve as a reminder that evil doesn't exactly follow the rules. In this article, we take a look at five terrifying examples where exorcisms went horribly wrong, each leaving in their wake destruction, questions, and an intense feeling of foreboding. These are not your standard spiritual triumphs; they're eerie reminders of what can occur when darkness won't be driven out.

Times an exorcism in a horror movie didn’t go as expected

1. The Exorcist (1973) – Father Merrin’s Unexpected Fate

The Exorcist (1973) | Image Source: Warner Bros. Pictures

When one thinks of botched exorcisms, The Exorcist comes to mind. While the ceremony to rescue Regan was supposed to be victorious, Father Merrin's untimely death took audiences aback. The veteran priest, who had battled demonic powers already, merely faints off-screen; no showdown with the devil. It wasn't the demon's defeat but the cost of humanity that made the scene so horrific. The torch then falls into the hands of Father Karras, whose frantic, self-sacrificing action turned the story from a triumph of faith to one of heroic tragedy. This was an unexpected twist that introduced a dark realism most exorcism movies avoid.

2. The Last Exorcism (2010) – The Demon Was Just Getting Started

The Last Exorcism (2010) | Image Source: Lionsgate

This mockumentary horror movie kept viewers lulled into believing it was debunking exorcisms until all hell broke loose in the last few minutes. Reverend Cotton Marcus thinks he's revealing staged rituals as a scam until he runs into a girl who's actually possessed. Following a seemingly effective exorcism, everything seems peaceful until Cotton strolls into a hellish forest ritual and sees a genuine demonic birth. The surprise wasn't merely that the exorcism didn't work, but that it wasn't even coming close to working. The climax turned the whole film on its head from skeptical horror to cosmic terror and left viewers stunned.

3. The Exorcism of Emily Rose (2005) – A Courtroom Couldn’t Save Her

The Exorcism of Emily Rose (2005) | Image Source: Screen Gems

What starts out as a horror film quickly morphs into a courtroom thriller, but the surprise? The exorcism wasn't successful, well, not exactly as anyone might have wished. Emily Rose dies, and the priest is on trial for her death. The scenes of the exorcism are frightening, but the consequences that follow are what truly linger. Was she sick in the head or really possessed? The exorcism's failure doesn't stop with death; its consequences go legal, moral, and theological, demonstrating that not every war between good and evil concludes with spiritual triumph or movie resolution.

4. The Conjuring: The Devil Made Me Do It (2021) – The Demon Just Switched Hosts

The Conjuring: The Devil Made Me Do It (2021) | Image Source: Warner Bros. Pictures / New Line Cinema

Throughout the graphic opening exorcism scene, everybody believes that young David Glatzel is cleansed until it's discovered that the demon had possessed Arne Johnson. This ghoulish bait-and-switch reveals that exorcisms aren't always a tidy solution. The demon departs from the boy, only to cause hell elsewhere, setting off a true-crime-inspired murder trial. The uncertainty of the demonic presence keeps both the characters and audiences in suspense, demonstrating that even experienced demonologists such as Ed and Lorraine Warren aren't always ready for what comes after a "successful" exorcism.

5. Hereditary (2018) – A Ritual Disguised as an Exorcism

In Hereditary, what appears to be a mourning mother's frantic bid to reach her daughter descends into something sinister. Annie's assumption that she's conducting a ritual of spirit-cleansing grief and perhaps even a ghost becomes exactly the opposite: a summoning of King Paimon. The would-be exorcism doesn't fail because it failed, but because it was never intended to work. It was only a portion of a larger, infernal scheme that destroyed her entire family. The twist is existential: evil wasn't driven out; it was invited in.

Exorcisms in horror movies are usually portrayed as a last resort, but, as these five tales illustrate, they do not always bring peace. Rather than closure, they leave devastation, further mystery, or even a wide-open door to more evil behind. These botched or distorted rituals remind us that in horror, nothing is certain, particularly salvation. The uncertainty of these moments heightens the genre, testing our limits and defying our notions of spiritual victory. Whether the evil remains, changes, or takes another soul, these exorcism scenes demonstrate that when religion fails, the darkness is quicker than ever to step in.