Nomura is first seen discussing Mondo Island with Carl Nelson. The two eventually decide to stop there on their voyage through the Indian and Pacific Oceans. When they arrive on the island, Nelson, Nomura, and Susan Watson are bade to leave by a mysterious native. Jiro and his superior begin to trek up the mountain to see what he is upset about. Part way up the mountain, Jiro and Nelson hear Watson screaming, and they head back down the mountain to discover that she is being attacked by Gorosaurus, and protected by Kong. After she escapes from the gargantuan ape, Jiro and Nelson lead her back to the ship. Once they are on board, they believe they are safe, but they are soon proven wrong when it is discovered that Kong is seeking Watson, and is now shaking the boat violently. Watson is eventually sent up to ward him off, and Jiro remains just inside the submarine's hatch with a gun in case things went wrong. Shortly after leaving King Kong behind, the ship is summoned to the Arctic by the Mysterious Doctor Hu. When they arrive at Hu's base, Nelson, Jiro, and Watson are taken prisoner after refusing to help Hu control Kong. Jiro and Watson are subjected to torture by the way of the cell's temperature being lowered to zero degrees. During his time in the cell, he grows closer to Ms. Watson. The two are eventually saved by Carl Nelson, just before King Kong escapes from his underground prison, causing the base to collapse. Jiro then sails with Nelson and Watson to Tokyo (where Kong where headed) to try and keep him from destroying the city by fighting Mechani-Kong. The robotic double eventually kidnaps Watson, and takes her to the top of Tokyo Tower. Kong eventually gets her back, and leaves her on a lower level, where Jiro goes to retrieve her. Jiro is presentas Kong swims back to Mondo Island.