A photorealistic 3D anime illustration from a medium shot and side-angle view, featuring two beautiful identical mermaids swimming gracefully side-by-side in a deep underwater setting at nighttime. Both mermaids possess flowing, long blue hair that drifts weightlessly in the current and luminous blue eyes; they are depicted with serene expressions, their hands gently gliding through the water in synchronized swimming motions. Their iridescent blue fish tails shimmer with intricate scales, reflecting the dim light. The environment is a dark, midnight-blue oceanic abyss filled with bioluminescent flora, floating plankton, and distant coral reefs that cast a soft, ethereal glow. The atmosphere is serene and mysterious, characterized by cinematic lighting, deep blue and indigo color palettes, a slight depth of field focusing on the mermaids, and shimmering light rays filtering down from the distant surface.
