James Wan's 2010 film Insidious, in a way, helped set the groundwork for the trends that horror would find itself firmly engaged in once the decade kicked off. While one may hear some horror buffs say that the sequel is the scariest of the movies in the seriesInsidious is an important entry in modern horror, especially when you look at the subgenre it belongs to - the supernatural realms of demonic possession and haunted houses.

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The film is also notable for using some interesting concepts that really hadn't been tackled in horror before, like astral projection. Those themes and the execution of the film, in general, make for one very scary watch. Take a look at the 10 scariest moments!

What Dalton Sees In The Attic

Sometimes in horror movies, it's more about what you don't see than what you do. This becomes increasingly evident in the sea of jump-scares that was horror in the early 2010s.

While this movie might have been partially responsible for that, it's important to note the restraint that the filmmakers used when they show us Dalton's initial encounter with whatever it is that ends up putting him in a coma at the beginning of the film. The resulting scene is eerier than it is scary, but this scene still packs a powerful punch.

"I've Never Seen Anything Like It"

While this scene might not be viscerally disturbing like a lot of the frightening scenes to follow, the pure anguish of watching a parent realizing that there's no hope for their comatose son is unparalleled in the film.

This scene definitely owes quite a bit to The Exorcist, being reminiscent of the scene where Regan's mother realizes that neither medical doctors nor psychiatrists have a single clue as to what's afflicting her daughter.

The Baby Monitor

This film does rely on exploiting the fears that come with parenthood, which is something that doesn't get talked about nearly enough. One of the scenes that highlight this is when there are multiple frightening happenings one after another. The first thing that happens is that a voice shrieks "I WANT IT NOW!" over the baby monitor.

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Shortly thereafter, Dalton's mother notices a bloody handprint on his sheets and an apparition crouched in the corner of his room. She almost immediately realizes the "thing" in Dalton's room probably isn't human, showing us exactly what kind of supernatural thrills we're in for.

It's Still Here

Anyone familiar with stories of real-life hauntings knows that if you can't handle it anymore, you pack up and you move out of the house with the things that go bump in the night, and then you should be all good.

Besides the trauma, you should be safe once you've settled down in your new house. This, unfortunately, is what happens in Insidious, though, since the spirits are attached to a family member and not the house.

Tiptoe Through The Tulips

There's a song during one sequence in the film that seems out of place and that is likely the intention of the filmmakers. The song in question is "Tiptoe Through The Tulips" by Tiny Tim. Tiny Tim himself was a bit of an odd character, originally seen as a sort of comedy musician, only to be relegated to the realms of outsider music as time went on, no longer appreciated for his novelty.

What made him so novel was his high-pitched crooning, his ukulele instrumentals, and strange appearance. In terms of the film, the juxtaposition of his whimsical music and the suspense of the situation only drive home the scares.

The Red Man

There's a specific scene that stands out in most people's minds when they talk about Insidious. When one looks at the scene as a still image, it doesn't seem as scary, but when the audience sees the figure of the red-faced man that's later identified as a demon, it stays with them for a while.

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He doesn't pop up at night while someone is alone, but in the middle of the day in a group of people. That's what makes this scare so effective.

What Do You Want?

One of the most effective parts of the whole film is when both the viewer and the cast of the film realize that all of the supernatural disturbances they've been experiencing aren't completely unrelated phenomena.

When one of the spirits tells the family that it's Dalton they're after in one of their dreams, it only becomes that much more real thinking back on what the doctors said about their son and how they're really not sure why he's comatose.

Last Night I Watched Myself Sleep, And Then I Flew Away

One of the situations that really hits the family and tells them that their spiritualist friend isn't just some new-ager making things up is when they find a drawing by Dalton that tells them exactly what they need to know to move forward and appreciate the situation for what it is.

The drawing shows two different figures: one is a child laying in bed, and the other is the same child looking back on himself with the caption "Last night I watched myself sleep and then I flew away." At this point, the family's worst fears are confirmed.

Why Josh Doesn't Like Pictures

One night, while going through an old photo album, the audience sees that Josh is being followed by a particularly horrifying old lady who lives in The Further. As they go through the pictures, getting closer and closer to the present day, we find out why Josh was camera-shy.

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He also had an intelligence attached to him when he was little, who hovered closer and closer in every picture. Somehow, the spirits latched onto his son who had the same abilities.

"Renai, I'm Right Here"

At the end of the film, after "Josh" has come back from The Further and Dalton is safe, the audience gets some subtle hints that maybe it isn't Josh who came back. Looking at his fingers as he comforts his wife, viewers see that they are gnarled and dirty, like those of a certain old lady.

After the credits, anyone who decided to let the film play long enough gets a little peek at the old lady blowing out a candle where Josh was, as the screen fades to black.

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