While humor is still in play in this season, the tone turns darker. Sam and Dean's relationship is more fragile than before, with Dean not entirely trusting Sam at first, wondering how Sam could have believed a demon (Ruby) over his own brother. In addition, Sam is dealing with his demon blood cravings, which the show treats as an addiction.

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Apart from their inner and brotherly turmoil, there are some truly scary moments that make us jump or linger in our memories of the episode. Read on to find out which ones are the scariest.

The Babysitter, Episode 6

Jesse Turner looking sad in Supernatural

Supernatural often delivers its scariest moment (or one of the scariest moments) of the episode at the beginning. This is the case for episode 6. A couple returns to find their babysitter asleep on the couch. However, when the father goes to wake her in order to drive her home, he notices something is wrong. Nudging her over, he finally sees her head, bloody and scratched through to the brain. It is a harrowing sight, causing the father to scream.

This is the episode where we met Jesse, a child who is half-demon and half-human. Jesse has amazing powers, and his beliefs come true like how itching powder (a prank) will lead one to scratch their brains out. He's not an evil kid; he just doesn't know he's doing it.

Hellhound and Jo, Episode 10

Ellen and Jo dying in season 5 supernatural

Sam, Dean, Bobby (from afar), Ellen, and Jo go on a mission to take Lucifer down. During the first stage of the mission, the demon Meg (an enemy who later becomes an ally) releases the hellhounds. Fresh from our memory of Dean being ripped to pieces by the hellhounds, we are already on edge. There is something about an invisible foe that is especially scary. We hear the growling and sense the viciousness.

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Jo takes one for the team, and while she isn't as ripped apart as Dean was, she ended up being gutted enough not to survive.

Gabriel and Lucifer, Episode 19

Mark Pellegrino as Lucifer and Richard Speight Jr as Gabriel in Supernatural

Sam and Dean end up being led to a hotel in Muncie, Indiana--what more peculiar place to be than in the heart of Middletown America. Also, peculiar is that the hotel is full of gods from different religions. They are pondering the Apocalypse and what this means for them. In addition, they kill the hotel guests for their food (these are scary moments).

However, the scariest moment is when we think that Lucifer has killed our favorite archangel, Gabriel. It seems pretty definite, but luckily, Gabriel is a trickster and lives to tell the tale of another day.

Sam and Dean Shot, Episode 16

Once other hunters learn that Sam is the reason that the Apocalypse started, they are not pleased. Two angry hunters show up in Sam and Dean's hotel room to kill Sam. Ultimately, they kill Dean, too, since they know that Dean will go after them.

We suspect that the brothers will come back, but this was pretty scary. Besides a crazed Gordon, hunters often left the brothers alone, considering the brothers a part of the hunter family. This one act shows that fellow hunters no longer recognize Sam as one of their own.

Croatoan Little Girl, Episode 4

Croatoan, Supernatural

Dean is sent to an alternative world where he is meant to see what would happen if he doesn't become Michael's vessel. Most of the humans are infected by the Croatoan virus. Of course, he doesn't know this at first when he spots a little girl crouched by her teddy bear on the street. He thinks that she needs help as he calls out, "Little girl, are you hurt?" Bent over a broken mirror, a saliva trail of blood drops from her mouth as if she had just eaten, and then she grabs a piece of the mirror to attack him.

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Equally as scary is the future Dean, a Dean of no empathy or compassion, willing to sacrifice his friends. Season 5 Dean would never do that, but Season 15 Dean is starting to resemble this futuristic version, especially in his treatment of Cas.

The Wraith, Episode 11

Sam and Dean enter an insane asylum to help an old hunter, Martin, who was a friend of their dad's. People have been mysteriously dying.

Dean and Martin finally find the wraith feasting on the brain of one of the humans. The wraith has a long needle-like appendage that she drills into the human's crazy brain, literally sucking it dry. While the true image in the mirror of the wraith was scary; this needle-like appendage sucking a human's brain was even creepier.

The Scary Kids at the Convention, Episode 9

We love when Supernatural goes meta and pokes fun at itself. This episode centers around a convention where fans of Chuck's books are there to LARP as if they were Sam and Dean investigating a haunting. However, the location that was chosen for this event was the setting where a real tragedy happened, and it has real ghosts.

The scariest are three boys, who seem innocent enough until they are freed from the ghost that was keeping them under control. One of the Supernatural fans runs into the boys. Mockingly, he says aloud, "Yeah, how original, Supernatural bringing you more creepy children. Sigh." While very true, these children are particularly creepy as they scalp him.

The Lucifer in Sam, Episode 22

Sam and Lucifer Supernatural

Sam accepts Lucifer's request to use him as a vessel. Although Sam believes that he's doing it to help others, it's clear that Lucifer lied. Dean, Bobby, and Cas rush to see if Sam is still in there. Lucifer quickly snaps his fingers to kill Cas, snaps Bobby's neck to kill him, and beats Dean almost to death. It seems scary--that there is no going back for our sympathetic Winchester, but Sam recovers and takes control briefly.

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He sacrifices himself to save others, jumping in the pit (aka Lucifer's cage) with Michael. At first, it looks like Dean is all alone, but Cas and Bobby come back. However, for a while, we were worried.

Dead Come Back to Life, Sheriff Jody's Son, Episode 15

The French Mistake - Sam and Dean do lines with Misha Collins in Supernatural

In Bobby's hometown, the dead come back to life. At first, the dead seem normal, retaining old memories and personalities. Then a switch happens, a hunger for human flesh.

Jody and her husband think their young resurrected son is normal-sick as he's running a high temperature. She steps aside to call the local doctor meanwhile her husband walks soup in to give to their son. Hearing a loud sound causes her to rush back into the room, and unfortunately, she sees her "son" deep into eating her husband. His face smeared with blood, he holds intestines while he walks slowly towards her.

Bloody Valentine and Young Lovers, Episode 14

The start of this episode is some of the scariest and grossest material we have seen on the show. We see two lovers meet and engage in what seems like a moment of passion. That passion quickly turns ghastly as the lovers start to literally eat each other up, taking bites of each other. Gross and scary, it is hard to watch a love that devours that intensely and literally.

Sam, Dean, and Cas discover that the pair of lovers were marked for each other via Cupid's arrow and symbols on their hearts. However, Cupid may have wanted them to crave each other, but not like that.

NEXT: Supernatural Sam and Dean's 6 Romances That Ended Too Soon (& 4 That Didn't End Soon Enough)