Mermaids

Unscrupulous fisherman John Mallick and his assistant Carlo are fishing with soda bombs in open water to harvest coral reefs when they notice a large creature thrashing in the water, Mallick shoots it and discovers that it's a merman. They attempt to collect the body but the vessel is knocked by a powerful force. Mallick sees a figure in the water, pointing a trident at him and he and Carlo escape, without the body of the merman.