Have you ever been home alone and heard a noise that made you just a little too uncomfortable? It was most likely nothing, just the sounds of your house settling or a branch hitting the window outside.

Some people, however, aren’t so lucky. You’ll probably want to investigate a little further next time you hear a sound go bump in the night—or, you know, get the heck out of your house—after you read about these creepy secret rooms people found in theirs.

Like one that contained hidden tapes.

Yeah, like the creepy tape they found in The Ring that ended up unleashing an evil spirit on anyone who watched it. We’re not saying that’s what happened here, but would anyone actually watch a mysterious set of tapes found in their walls knowing a movie like that exists?

This tale starts out with Reddit user LmbrJack, who made a post describing his discovery of a hidden area within his walls. In the small passageway, he discovered a tiny room that held two things: a briefcase and a safe.

He not only found multiple watches and some money, but also a set of video tapes, one of which was labelled with the word “NO” six times. According to an update the user posted on Reddit, he turned over the tapes to his local sheriff’s department and was asked to take down all of his posts related to his findings.

It wasn’t made clear whether or not he actually watched the tapes and knew what was on them, but better safe than sorry—if movies have taught us anything, it’s that you die if you watch anything suspicious you find.

Or an awesome hidden passageway that was actually hiding…

Mold. Like, tons and tons of toxic black mold.

A couple named Jason and Kerri Brown purchased their new home in 2015, and were shocked when they eventually discovered a secret corridor disguised as a bookcase. They were understandably thrilled and intrigued—after all, this is the kind of thing that leads people to buried treasure and hidden money, right?

Not so much. Within the passageway, they found a note that started off by saying, “If you’re reading this, then you’ve found the secret room!” That makes it sound much more exciting than the discovery actually was, though, because the note went on to say that the hidden area was filled with black mold—so much of it that the previous owner and his children were constantly getting sick from it.

The Browns immediately packed up their stuff and left the house behind, making sure to sue the agent who sold them the mold-infested house in the first place.

There’s also this creepy religious hideaway.

As if that isn’t already weird enough, it was also found under the floor, a detail that makes it that much spookier. When the Farla family moved into their new home, they noticed a large metal grate in the middle of one of their hallways, but didn’t think too much of it.

However, after living there for approximately three years, they finally decided the curiosity was too much for them and they removed the grate to see what in the heck was below it.

They got a little more than they bargained for when they found that it covered a staircase that led to a small stone room, one that had to be as old as it looked, as it was filled with rust and debris.

Oh, and that’s not even mentioning the giant stone cross that they found embedded into the floor of the room. Intrigued and more than a little creeped out, they consulted a local historian who told them that the room may have been used to house Catholics at a time when religious persecution was common for them.

And this peephole-ridden staircase.

Imagine if Harry Potter decided to use his spot beneath the stairs to spy on the Dursleys like a total creeper, and this is what you have. When a pair of people doing some house hunting made their way into the basement of this home, they discovered something pretty disturbing behind the basement stairs: The area had essentially been used as someone’s bedroom.

On the back of the stairs were notes that read “Stop watching me,” “No watching Isaiah through the hole,” and, most ironically, “No writing or drawing on the walls.”

Sure enough, they looked around the space some more and discovered that holes had been carved into the stairs so whoever stayed in that small room could look out—or maybe so everyone else could look in. Another Reddit user suggested it may have been a space used to allow the kids to vent after getting in trouble or getting too worked up, but the space definitely gives off a more sinister vibe.

This castle is clearly hiding a lot of things.

Singer Castle, which was built in 1896, has been referred to as “The Castle of Mysteries” by The New York Times. It’s located on Dark Island (which despite its ridiculous name is actually a real place) in Hammond, New York, by a man named Frederick Bourne, who was the president of the Singer Sewing Machine Company at the time. It turns out that the castle was filled with hidden corridors, booby traps, and even a dungeon. Apparently Bourne was either insane or just super protective of his sewing machine secrets.

There’s a sliding wall that reveals a hidden staircase in the home, a picture that allows whoever is behind it to eavesdrop on whoever is in the room it faces, and there’s even a treasure trove that is hidden by a latch that only appears to be a coat hook on the surface. Oh, and as previously mentioned, there’s a long corridor that takes you to a dungeon-like area with black gates.

Believe it or not, you can actually book a suite there to stay the night, go for a quick tour, or even have your wedding there. Just don’t go wandering around at night…

Don’t trust a house with a hidden staircase.

An Imgur user who goes by the name TwoBiteBrownie doesn’t like staying home alone very much anymore and it’s all thanks to an accidental discovery he made after he and his brother were wrestling too hard one day.

They were jumping around and fighting on their parents’ bed when TwoBiteBrownie fell off and hit his parents’ bookcase just a little too hard. To his surprise, the bookcase actually opened up, revealing a hidden passageway that had been behind it all along. Plucking up the courage to investigate, he and his brother traveled down the spiral staircase behind the bookshelf and found something even creepier than their initial discovery—a crawlspace, and one that had clearly housed a living person somewhat recently.

In the hidden space, they found pieces of candy from Halloween, and a banana peel that looked pretty fresh. “Someone was living in our walls,” TwoBiteBrownie said in his post. “That is my Halloween candy. Someone came into my room, took from my bag and brought it back in here.” He said they quickly realized the severity of what they had discovered and got out of the room as fast as they could. They told their parents and alerted the authorities, who later found some dolls, a skeleton key, and a carving of an elephant in the space, as well.

The most terrifying part, though? There weren’t any other entrances that lead to the space, meaning that the person had to have gotten in their house to make it down there.