Pierre is a researcher who showed up in the episode "Type Casting." He and his colleague Marie were collaborating on a research paper about Sudowoodo's typing—specifically whether it was Rock-type or Grass-type. The problem was they couldn't agree. Pierre was convinced it was Rock-type based on what his reference materials said, while Marie disagreed.
When Ash and friends helped them track down an actual Sudowoodo to test their theories in the lab, Pierre got impatient and grabbed a hose to spray it, trying to prove his point. That backfired—the Sudowoodo just ran off. After Team Rocket showed up and caused chaos, things became clearer: Sudowoodo used Mimic to copy other Pokémon's moves, including Grass-type attacks, which is what had confused Marie. Pierre's original assumption turned out to be right—Sudowoodo is indeed Rock-type.
By the end, both researchers owned up to their stubbornness and decided to keep working together on their projects.
Content compiled by AnimeList.moe from publicly available sources.
