In a world plagued by the terror of the 'Others,' enigmatic creatures descending from the sky to consume human brains, a discovery of psionics unveils a weapon against these monsters. The nation responds by forming the Other Suppression Force (OSF), also known as the Scarlet Guardians, comprising gifted individuals with extrasensory powers. Among the elite recruits celebrating their entry into this force is Yuito Sumeragi, the resolute son of the nation's founder, inspired by a childhood rescue by an OSF member. As Yuito navigates the complexities of his new role, he is startled by a striking resemblance between the savior from his past and one of his colleagues. Yet, this personal revelation pales in comparison to the looming threat of a clandestine plot that could upheave the very foundation of their society.