In 1999, a group of young friends discovered the Undernet, a secret architecture hidden beneath the internet that allows users to record, share, and experience pure violence and cruelty. After suffering a traumatic tragedy, they managed to seal it away, vowing never to speak of it again. Decades later, the Undernet re-emerges through a terrifying cyber-entity known as PH34R, spreading extreme violence across the globe and forcing the surviving friends to reunite and confront the digital nightmare they failed to destroy.