Okay I've asked this question before, but I want to refresh it. When I was in elementary school during the mid nineties, I saw a school presentation. The actors were all adults who performed for the students in the school. It was about a woman who went underwater. She encountered a dolphin, who had a whale for a mom named mother mother. There are enemies that they face. The enemies are a grim reaper like fish that is followed by three smaller grim reaper fish. Their leader is this white ghost like demon fish. The white demon fish kills mother mother with a weapon that is later revealed to be a net. Then the woman and the dolphin are able to repeal the white demon fish by chanting an incantation. I don't remember exactly what it says but it goes something like sea magic of the deep blue sea, sea magic, she of the sea. Something like that. Then a sea goddess of the incantation appears and then reveals herself by taking off her mask. Does this sound familiar.