A sinister aquatic demon with a statuesque humanoid form and strikingly angular features emerges from the depths, its skin a mesmerizing shade of iridescent blue. With an intense, furrowed brow and a mouth set in a terrifying grin that reveals needle-like sharp teeth, its presence is both captivating and fearsome. Surrounded by an eerie, underwater landscape that shimmers in the dim light, the scene is captured with cinematic precision using Unreal Engine 4, the lighting casting dramatic shadows and highlighting the demon's otherworldly essence.