Ruined Underwater Temple

Publisher's blurb: Different schools of fish dart between ancient pillars and colourful growths of coral in this ruined underwater temple. Seaweeds sway in the water’s currents, sticking to the intricately tiled floor and walls. Light dances across the floor, highlighting the darkness in the hole between levels. Sharks swim down there, amidst the shadows and sand. What are they guarding?