A film about the problems of the development of the riches of the world ocean. In the center of the story is the journey of the journalist M. Aleksandrov on the floating floating vehicle "Kalmar". Dolphin with a film camera on its back. The raging ocean. Research vessels "Vityaz", "Vladimir Komarov" at sea. Scientists take a soil sample from the seabed, dip measuring instruments into the water. A group of scuba divers and journalist M. Alexandrov aboard the underwater house "Chernomor". Cabin. Scientist Thor Heyerdahl, who swam across the ocean on a balsa raft, talks to a journalist. Loading "Squid". Monkey on deck. Launching "Kalmar" into the water. Squid deck, halyard, hatch. An oceanologist examines seaweed taken from the ocean. Algae at the bottom of the ocean. The scuba diver measures the length of the algae. Inhabitants of the deep sea. Red corals, blue and purple stones at the bottom. Whales on the surface of the water. The Vostok vessel. Fishing vessels. Fish net. Catching squid. Crabs. Scallops. The scuba diver collects galturium. Shark. Ichthyologist at work. Vat with caviar. Fry. Small sturgeons swim in the water. The coast of the island is covered with seals. Seals in the water. Cubs. Dolphins at the "Squid". Experiments of scientists with dolphins. Octopus. A shark swims by. Big turtle. Kislogubskaya power plant. Power plant site under water. Ocean floor. Spiral trail of an unknown animal. Dry ocean floor. Mariana Trench. Eruption of an underwater volcano.