Listen to “YouTube” on Spreaker.
Imagine this.
You’re sitting at your computer late at night, the glow of the screen painting the room in soft blue light. You’re clicking around YouTube, maybe looking for a new song, maybe just wasting time, when you stumble across a channel you’ve never heard of before. At first, it looks normal—thousands of videos, all uploaded recently.
But the titles? They make no sense. Strange symbols. Random words. Numbers scattered everywhere.
Curious, you click on one of the videos.
The screen is pitch black. No picture, no moving image, just blackness. Then a sound begins to play. It’s a distorted noise—sometimes like a voice, other times like a broken radio signal, or a low hum that makes your stomach twist.
You click another video. Same thing. Black screen. Strange sound. Then another. And another.
You realize this channel isn’t like anything else on YouTube. It feels… wrong. Like you’ve just walked into a place you shouldn’t be.
This is the story of Unfavorable Semicircle—one of the most chilling and unsolved mysteries on the internet. A YouTube channel that uploaded thousands of cryptic videos that nobody has ever fully explained.
And by the end, you’ll see why so many people believe it wasn’t just some weird art project, but possibly something much darker.
The Discovery
Unfavorable Semicircle first appeared in 2015. Nobody knew who created it. At first, it didn’t attract much attention—just another strange corner of YouTube. But soon, people started to notice something very odd about this channel.
It was uploading videos constantly. Not once a week, not once a day—dozens, sometimes hundreds of videos in a single day. Each one was short. Some only lasted a second, others maybe a minute.
The titles looked like gibberish. For example: “A0048,” “ps64,” “n a.” Sometimes just random symbols. No two titles seemed connected.
And the content? Always the same: a black screen, with bizarre audio. Some sounded like electronic beeps. Others like whispers buried in static. Sometimes a deep rumbling noise that made people feel uneasy, like it was vibrating inside their chest.
There was no description, no explanation, nothing. Just an endless flood of cryptic videos.
People who stumbled onto the channel were hooked. What was this? Who was making it? And most importantly—why?
The Audio
When people started analyzing the videos, things got even stranger.
The audio wasn’t just random noise. At least, it didn’t sound that way to everyone. Some thought it might be coded messages, hidden inside the static. Others believed it could be computer-generated tones meant for machines, not humans.
One video in particular creeped people out. The sound was a distorted voice, so buried in layers of fuzz and static that you couldn’t make out the words. But if you listened carefully, it almost sounded like it was calling out numbers.
Other clips were so high-pitched or so low that they hurt your ears or made you feel dizzy.
Viewers described the experience as unsettling. It wasn’t like watching a normal video. It felt like you were hearing something you weren’t supposed to hear.
Theories Begin
Pretty quickly, the internet exploded with theories.
Some thought Unfavorable Semicircle was an ARG—an alternate reality game. These are online puzzles designed to lead players through riddles, ciphers, and mysteries. Games like Cicada 3301 had done this before, using cryptic messages to recruit brilliant minds. Maybe this was another one.
Others believed it was a numbers station in disguise.
Back in the Cold War, secret radio stations would broadcast nothing but strange sounds or voices reading numbers. These were actually coded instructions for spies in the field. Anyone else who tuned in just heard meaningless noise.
Could Unfavorable Semicircle be the YouTube version of this? Maybe spies were getting instructions hidden inside the strange tones.
But then, darker theories started spreading.
Some people thought the channel was a test by YouTube itself. Like some experiment in how the platform handled endless uploads, or how people reacted to weird content.
Others whispered about even more disturbing possibilities—maybe it was a way to send hidden signals for something criminal. Or worse, something dangerous.
And then, one day, things took an even stranger turn.
The Reddit Connection
The mystery really blew up when people started posting about it on Reddit. A community formed, with users analyzing the videos frame by frame, sound by sound, trying to find patterns.
Some thought the titles weren’t random at all. They noticed that certain strings of numbers and letters seemed to repeat, like they were part of a larger code.
Others believed the audio contained spectrogram images. That’s when you turn sound into a picture to see if hidden shapes appear. People tried this with the Unfavorable Semicircle sounds, hoping to uncover secret messages or symbols.
But nothing ever came out clear. No secret words. No obvious pictures. Just more confusion.
And then something happened that made the whole thing even more unsettling.
The Ban
In early 2016, without warning, YouTube deleted the Unfavorable Semicircle channel.
It was just gone. Thousands of videos. Erased overnight.
No explanation. No announcement. Nothing.
This sudden removal only fueled the fire. Why would YouTube step in and delete it if it was harmless? Why not just let it stay up? Unless… it wasn’t harmless at all.
Some believed YouTube was pressured to take it down, maybe by a government agency. If it really was a numbers station for spies, authorities would want to shut it down fast.
Others thought maybe it was broadcasting something illegal, or even dangerous.
But because the channel was gone, we may never know.
Aftermath
Even though the original channel disappeared, the mystery didn’t die. People had downloaded and archived many of the videos before they vanished, and they’re still floating around online today.
Every so often, a new theory pops up. Some claim it was an art project, designed to creep people out and make them ask questions. Others still hold to the spy theory.
But here’s the thing—no one has ever come forward to take credit. No artist. No game company. No group. Nothing.
And usually, with projects like this, someone eventually says, “Yep, that was us. Here’s how we did it.” But not with Unfavorable Semicircle.
It remains one of the strangest, most unexplained YouTube mysteries ever.
Why It Matters
The reason Unfavorable Semicircle sticks in people’s minds is simple: it feels wrong.
The internet is full of weird content. But most of it, you can figure out. A prank, a hoax, a piece of art. This? It doesn’t fit neatly into any box.
It was too consistent, too massive, and too unexplained. Thousands of videos, endlessly uploaded, with no sign of stopping—until YouTube pulled the plug.
And the sounds? They get under your skin. Even if you don’t believe in hidden codes or spy messages, just listening to them feels eerie. Like you’re tapping into some secret signal not meant for human ears.
The Unsolved Puzzle
So, what was Unfavorable Semicircle?
A secret spy communication system?
A complex alternate reality game?
A bizarre art experiment?
Or something else entirely?
No one knows. And that’s why it’s so chilling.
Because the videos are still out there. The strange noises still play. The cryptic titles are still waiting to be decoded. And maybe, just maybe, the people behind it are still out there too—watching.
Closing Thought
The internet is filled with mysteries, but some, like Unfavorable Semicircle, aren’t just unsolved—they feel alive. Like they’re waiting for someone to figure them out.
And maybe one day, someone will.
But until then, if you find yourself wandering late at night on YouTube, clicking through strange channels, and you hear that static-filled voice whispering through your headphones… you might want to ask yourself:
Did you just stumble on a mystery?
Or did the mystery stumble on you?
