As they fly over the Sea of Mystery, Flash & Dr. Zarkov are forced to eject from their rocket when strange mysterious magnetic rays strike their ship, forcing it into a crashlanding. The heroes are pulled beneath the sea and into the beautiful city beneath the sea, Coralia, where they are greeted by Queen Undina. As Flash is given a tour of Coralia by the Queen they are attacked by Ming's Gillmen. They soon realize that Ming plans a large scale underwater attack on the city...
