At the beginning of the 18th century Emperor Peter I issued a decree to equip an expedition to the far northern borders of the Russian state. The legendary navigator Vitus Bering led this mission. He divides his people into several teams. Officer Vasily Prontchishchev took command of one of them. In this very difficult expedition on the Siberian rivers Lena and Yenisei he was accompanied by his wife Tatiana. One of the members of the expedition was Semion Tcheliouskine, then still unknown but who would later become a famous sailor. Incredible discoveries and insurmountable trials awaited our heroes. The film is based on real events.