Filming is dedicated to the unique project 661 submarine K ("goldfish" or "papa"), built at the plant No. 402 ("Sevmash") in Severodvinsk. This documentary includes filming: a solemn meeting at the plant on the occasion of the order No. 501 for the construction of a submarine on December 28, 1963. Speeches by the rally participants; among the speakers - the designer of the submarine, academician Hero of Socialist Labor N.N. Isanin. Production processes in the shops of the plant. Workers are mounting a sign with the NDP "For our Soviet Motherland! Submarine K project 661, factory # 501, laid down on December 28, 1963 in Severodvinsk at the state order of the Red Banner of Labor, factory # 402" on the hull of the boat.