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The construction director (Japanese: 監督 Director) is a character of the day who appeared in Dig Those Diglett!. He was never given a proper name in either the Japanese or English version.
A construction director was fed up with the Diglett that were interrupting the Gaiva Dam project. At one point, he was so desperate to get them removed, he recruited Trainers from all over Kanto to help eliminate them. Among them were Ash and Gary. However, when released, all the Pokémon went back into their Poké Balls. Director was even more baffled by these latest developments, and it only made him more annoyed.
Later that night, he observed the Diglett and Dugtrio helping maintain the environment. Realizing that the Gaiva Dam was getting in their way, he decided to abandon the project and leave the forest alone.