Have you ever heard of "Spotter.mp4?"

Supposedly, it's a video that can appear to anyone on any video sharing site. You can recognize it by the title, a thumbnail containing two eyes on a completely black background, and the lack of an author listed anywhere. The video itself contains about thirty seconds of just the eyes from the thumbnail staring at the screen, backed by the audio of heavy breathing, occasional swallowing and, near the end, what can only be assumed to be someone loudly licking their lips.

At least, this is how people who claim to have seen the video described it prior to their deaths, because anyone who views Spotter.mp4 will spontaneously die within hours of unknown causes. Some people who haven't seen the video themselves, but say they knew someone who did, have told stories of finding the corpse of the viewer in their home, and then later learning that it was entirely drained of blood and missing several vital organs, all seeming to have mysteriously vanished from their body.

Another property the video is said to have, is that once it appears, it won't leave you alone. You can ignore it, remove it from your recommendations, switch accounts and even use a different device, but it will always show up again sooner or later. It's clever, too. It can disappear for months at a time, only to reappear just as you forget about it, and guess the position where it's most likely for you to accidentally click on it based on your mouse movement. If evaded for too long, it'll even go as far as to disguise itself as other videos, leaving nothing but its eyes to tip you off. It's as if it has a mind of its own, and desperately wants to be seen.

Of course, all of this is just rumors. Spotter.mp4 has never been proven to truly exist, and even if it did, it's unlikely that you would ever come across it in your lifetime. Be warned, however: just because you haven't seen Spotter.mp4, that doesn't mean it hasn't spotted you.