Robert Englund was originally offered the role of Dr. Corenthal. Despite expressing his admiration and support for the series, he respectfully said no.
The creators have stated that, though the series never reveals them, it is possible to learn HABIT's motives from closely analyzing the episodes. As of 2018, they have confirmed that some viewers have discovered them.
The entire series was originally supposed to be one season, with the bulk of filming taking place in the summer of 2010. When Jeffrey Koval introduced the idea to expand the series into an ARG, allowing the audience the potential to unlock several ongoing subplots, they realized the story had become too large to film in one year with their small budget.
Of the series' cast, there is not a single one who appears in every episode.
The first scene ever filmed for the series was the shot of Evan's hand in the car window, from Introduction (2010); the last scene ever filmed was the dinner scene from The day the world ended (2018).