No one could pass by the treasure chest they found, and this is perfectly clear. Therefore, it is not surprising that even a mermaid bought a chest. She swam past an old flooded pirate frigate and suddenly noticed a sparkle among the wooden, mossy debris. Sailing closer and pulling the planks away, the beautiful sea maid pulled out a weighty chest. But the trouble is, it is closed, and the key is not visible nearby. Help the heroine in the game Underwater Treasure find the key in countless wealth. Take a look around, solve all the puzzles, collect the necessary objects and there is a key.