Viral YouTube horror sensations are officially taking over Hollywood. Following the massive box-office dominance of The Backrooms movie adapted from Kane Parsons' (Kane Pixels) viral YouTube series–studios have greenlit feature films for both Siren Head and The Mandela Catalogue to capitalize on the internet-horror boom.

According to The Hollywood Reporter, Warner Bros. officially acquired the rights to Siren Head on 2 July after winning an intense five-studio bidding war. The viral horror phenomenon centers on a towering, skeletal cryptid with two sirens as a head. Brian Duffield, the director of No One Will Save You, is set to direct the feature, teaming up with Barbarian and Weapons filmmaker Zach Cregger to co-write the screenplay. 

Meanwhile, Deadline reports that an adaptation of The Mandela Catalogue is also in active development. A cornerstone of the "analog horror" subgenre, the original series focuses on grotesque, shape-shifting entities called "Alternates" that infiltrate people's daily lives. Fresh off his recent sci-fi thriller Disclosure Day, Hollywood legend Steven Spielberg will produce the film under his Amblin Entertainment banner alongside Amazon MGM. The movie will be directed by the series' 22-year-old creator, Alex Kister, who co-wrote the screenplay with Tyler Clifton. 

While official premiere dates have not yet been announced for either film due to the projects being in early development, studios are expected to fast-track production to strike while the internet-horror wave is at its peak.

With internet-born urban legends proving to be massive box-office draws, fans are already looking to the future with many hoping this wave of high-profile adaptations will eventually lead to a definitive cinematic redemption for Slender Man.