The film stars Azita Ghanizada, Ryan O'Nan, Harley Quinn Smith, Chris Jericho, Justin Kucsulain, Jason Mewes, and Ralph Garman.

[4] The film was released as 5,555 exclusive non-fungible tokens on July 12, 2022, on Legendao, Secret Network's NFT minting platform.

When she sneaks into the school to investigate further, she uncovers hundreds of drawings and stories about Killroy, spiraling into insanity, its soon revealed to be a prank set up by the Janitor in order to scare her, revealing that once a year: Students disappear and, in order to save themselves, make a deal with Killroy to trick an adult into summoning him so he can claim a sacrifice.

In the fourth and final story, presented as a found footage film, a southern live streamer lures gay men for sex, then shames them on camera by insulting and attacking them, while viewers laugh.

In April 2014, Kevin Smith announced the Christmas-themed horror movie Anti-Claus, with a script based on the episode The Christmas Special of his Edumacation podcast.

Filming was initially scheduled for September 2014, with Tusk (2014) actors Justin Long, Michael Parks, and Haley Joel Osment returning as cast.

[16][17] The film also shot scenes in areas around Ringling College of Art and Design and Nathan Benderson Park, before moving to Longboat Key.

[18] In January 2018, Azita Ghanizada, Ryan O'Nan, Justin Kucsulain, Kathryn Parks, Brendan Ragen, Michael Perez, and Cindy De La Cruz were confirmed to be starring in the film,[8] while Andrew McElfresh, Tony Stopperan, Joe Restaino, Nick Morgulis, Jordan Monsanto, and Adam Yeremian signed on as producers.

[25] In April 2020, Smith revealed that the tone and style of KillRoy Was Here were inspired by Creepshow (1982), another comedy horror anthology film.