A film about the Hero of Socialist Labor, honored rationalizer of the Republic, locksmith of the Kaluga plant of motor transport equipment G.I.Sergeev. G. Sergeev sketches sketches of his future developments, at work in his home office. The city of Kaluga. Checkpoint of the vehicle equipment plant. Automatic mechanical workshop of the plant. Assembling the regulator relays. Water temperature sensors section. Conveyor for assembling electric motors. G. Sergeev examines the assembly process. Sergeev's automatic machine for bending ears. The collectors work on Sergeev's semi-automatic machines for cutting and driving silver into a biplate. Six-seater semiautomatic device for winding coils of Sergeev's regulator relay. Production line for bearing machining. Machine for winding anchors designed by Sergeev. Sergeyev's copyright certificates. Experimental laboratory engineers at work. Panel assembly area.