Humans say, mermaids are just a myth. In reality, on this earth, humans have only explored 5% of the ocean. The rest is a mystery. They don't know that in the vast and deep ocean, there is a beautiful palace—that the ancient Greek gods are real, not a myth but a forgotten history. Poseidon, God of the Sea, is still alive today, guarding his domain with his extraordinary power. He has many children, one of whom is Yvonne de Sereia, who then fell in love with a human, Willard van de Zee.