This episode focuses on the process of making giant ship propellers - from the initial stage when the copper alloy is cast into the mold, through the final steps which require manually planning the hole in the propeller where the shaft must be snugly fitted, to the hand polishing of the giant blades. These "human touches" ensure that the ships which transport goods around the world can journey efficiently and safely. To paraphrase Mr. Izutani who has been doing this job for 25 years: "Humans are still superior to machines."