Something Awful in the context of Red tape

The Slender Man (also called Slenderman, Slender, or Slendy) is a fictional supernatural character that originated as a creepypasta Internet meme created by Something Awful forum user Eric Knudsen (also known as "Victor Surge") in 2009. He is depicted as a thin, unnaturally tall humanoid with a featureless white head and face, wearing a black suit.

Stories of the Slender Man commonly feature his stalking, abducting, or traumatizing people, particularly children. The Slender Man has become a pop culture icon, although he is not confined to a single narrative but appears in many disparate works of fiction, typically composed online. Fiction relating to the Slender Man encompasses many media, including literature, art and video series such as Marble Hornets (2009–2014), wherein he is known as The Operator. The character has appeared in the video game Slender: The Eight Pages (2012) and its successor Slender: The Arrival (2013), as well as inspiring the Enderman in Minecraft. He has also appeared in a 2015 film adaptation of Marble Hornets, where he was portrayed by Doug Jones, and an eponymous 2018 film, where he was portrayed by Javier Botet.

Marble Hornets is an American found footage web series created by Troy Wagner, Joseph DeLage, and Tim Sutton. It is a pseudo-documentary based on the Slender Man online mythos. The first video posted to YouTube was on June 20, 2009, 10 days after Eric Knudsen made the original images of Slender Man on the Something Awful forums. The series follows film student Jay Merrick (Wagner) as he investigates what happened to the student film Marble Hornets, abandoned by its director Alex Kralie (DeLage) after encountering the Slender Man (called "the Operator").

There are 92 episodes on the Marble Hornets channel, with accompanying videos from a diegetic side-channel, totheark. As of late 2025, the series had over 700,000 subscribers and received 125 million views. The series also established the Slender Man symbol, which has since appeared in many other stories featuring the character. The reception for the web series has been mostly positive.