- O Baú De Maldições
- O Chamado do Gato - Uma História de Fantasmas e Coisas Piores
- O Ciclo Do Lobisomem E O Apocalipse De Elias
- O Cético
- O Fantasma Assassino
- O Homem que não estava lá
- O povo obscuro dos Capensis
- O Que Você Quer Ver
- O Satanismo Da Tribo De Dan
- O segredo de Blossom Rise
- O Sonhador Vigarista
- O vampiro da Ordem de Caim
- O vídeo amaldiçoado do whatsapp
- O Xá do Abismo
- O Xá Do Abismo
- O.P. #7 (The Horrors of War)
- Oak
- Oakland Manor
- Oakwood
- Obadiah Clegg
- October Omen
- October Surprise
- October Tales: Seven Creepy Tales
- Odbila 13. Hodina
- Odd Apocalypse
- Odd Things
- Of A Strange and Dark Vintage
- Of Flesh & Blood
- Of Ghosts and Dreams
- Of Grave Concern
- Of Spirits and Superstition
- Of Tangible Ghosts
- Of The Grave
- Of the Spirit
- Of Things Not Seen
- Off the Beaten Path
- Offerings for Arianrhod
- Oil Smudges
- Ojos de circo
- Ojos de circo
- Old Bones Secret Rain
- Old Church Ghosts- The Unseen Version
- Old Church Ghosts-Special Edition
- Old Haunts
- Old House of Fear
- Old Lady Mary
- Old Man's Beard
- Old Man's Lake
- Old Soldiers
- Old Spice Love Knot - A Nova Scotia Ghost Story
- Oldtown Fireside Stories
- Olvidada
- Ombre
- Ombres
- Ominous Winter
- On Ghosts
- On Hallow's Eve
- On Jack Thayer's Watch
- On Misery and Fallen Angels
- On Raven Wings
- On the Bridge
- On The Night Of The Christmas Eve
- On the Third Night
- Once Distant
- Once Over Lightly
- Once Upon A Ghost
- Once Upon a Gothic
- Once Upon a Magpie Moon
- Onde Ånder i Calle Goya
- Ondragon 4: Seelenflut
- One Hex of a Wedding
- One Hospital Nightmare
- One Hundred Candles
- One Morning, A Chest
- One Night In The Murder Bed
- One of These Nights
- One Second Beyond Twilight
- One Thousand and One Nights
- One Vibrant Hue
- One Who Saw
- Oni-Devils
- Only a Shadow
- Only Animals Allowed in Heaven
- Only Forever
- Only In Dreams
- Onschuld
- Oops An Incubus Got Me Pregnant!
- Ophelia, le vite di una ghost writer. Perversioni d'autore
- Ophis
- Oracle Bone
- Oracle V – Travels Through Other Dimensions
- Orb
- Ordinary World
- Orfanato Dos Sonhos
- Origins
- Os Amaldiçoados
- Os Contos Do Caso Abraham
- Os justiceiros
- Os Pertences do quarto negro
- Os Qontos Dos Infernos
- Os Zumbis da Calle Goya
- Osobliwy dom pani Peregrine
- OtherLife
- Othernaturals Book Three: Bloodfather
- Othernaturals Book Two: Lucid
- Our Eyes at Night
- Our Longest Night: A Short Story
- Out of the Blue Nights of Death and Desire
- Out of the Blue Whispers in the Dark
- Out Of The Night
- Out of the Night
- Owen Wingrave (1892)
- Owl Eyes Motel
- Ownership is Fatal
- Oxygen