The TV series Dark Secrets, from 3net Studios, begins each episode with a teaser prologue, followed by this ominous voiceover: “When an abandoned industrial building is cleared for demolition, a locked door is discovered in its basement. The door conceals an archive of strange and disturbing specimens, recordings, photos, and documentary films—compelling evidence of monstrous creatures and preternatural events. The documentarian’s whereabouts remain unknown. In his records, he identifies himself only as ‘The Teller.’ His investigations reveal a frightening world of dark secrets.” The series deals in strange, supernatural phenomena, presented in a classic documentary style. Eyewitnesses or survivors are...