Mysterious,
Intriguing,
Suspenseful,
Enigmatic,
Cryptic,
Ominous,
Sinister,
Macabre,
Grim,
Chilling,
Haunting,
Eerie,
Shadowy,
Uncanny,
Murderous,
Deadly,
Grimy,
Foreboding,
Bloodcurdling,
Unsettling.