The film tells about space navigation and communication systems in the fleet, about the International satellite search and rescue system "Cospas-Sarsat". Filmed by order of the USSR Ministry of the Navy. Part 1 Meeting of the members of the expedition of the British traveler Tim Severin, who arrived in Georgia while traveling along the route of the ancient Argonauts from Greece to Colchis on a replica of the ancient Greek ship "Argo"; among those meeting the traveler-researcher, TV presenter Yuri Alexandrovich Senkevich Training sailing ship "Comrade" at sea. Cadets climb the rope ladder. A group of cadets gets acquainted with space navigation equipment. Cadet at the helm. "Comrade" is sailing. Lighthouse in the sea. Cargo ship "Marshal Vasilevsky", passenger motor ship "Tajikistan", tanker "Moris Torez" and other ships at sea. Antennas on ships and ground stations. Navigation devices, other devices and ship control devices on the captain's bridges of various ships. The ship is at the pier. The boat is pulling the ship in tow. Members of the crew of one of the ships in the dining room at dinner, reading, playing chess. The icebreaker moves in the ice in the evening. Building, auditorium, simulators of the Leningrad Maritime Training and Research Center. Andrey Andreevich Yakushenkov, Candidate of Technical Sciences, talks about the center (sinhr.). The captain-mentor conducts a lesson on the training bridge, on which sailing at night is simulated. Part 2 Waves at sea. Seagulls. Cargo ships at sea. The helmsman, captain and other crew members on the bridge. Navigation devices. The radio operator at the equipment on the ship. Radio operators of the coastal radio center of the space communications system at work. The radio operator transmits the signal using Morse code. Chairman of the All-Union Association "Morsvyazsputnik" Yuri Sergeevich Acerov speaks about the initiative of the Soviet Union to create an international satellite communications organization "Inmarsat", about the importance of satellite communications (sync.). Antennas of the Inmarsat station. Signalers at work at the station. On the display screen, the correspondence of the ship's captain with the sea agent. The captain speaks on the intercom in English (sync.). A naval officer at work with a teletypewriter. Drill-down on the ship: fire on the ship, a sailor throws a radio beacon into the sea. Antenna and building of the station for receiving and processing information "Cospas-Sarsat" in Moscow. Signalers at work. Rescuers in boats descend from the ship into the sea. Radio beacon in the water. Coastal radar station in the Nakhodka Bay. The operator calls the ship's crew for communication (sync.). The crew of the ship on the bridge. The captain speaks on the intercom (sync.). Ukraine, Odessa region Ilyichevsk seaport. Communication station serving the port. Computer in the hall. Port cranes. Tractors on a railway cargo platform in the port. International ferry service Ilyichevsk - Varna (Bulgaria). Communication station employees monitor the movement of the ferry. The display screen connects the rails of the ferry to the railway in the port. Passenger motor ships "Tajikistan", "Kazakhstan", cargo ship "Aleksey Kosygin" at sea.