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J's henchmen are men who help Pokémon Hunter J in her crimes. They first appeared in Mutiny in the Bounty!.
Only two of J's henchmen are shown to have their own Pokémon. These particular henchmen catalog all of the Pokémon J has stolen and they appear to be the most important of them. One of them used a Golbat to battle Ash's Pikachu before Ash, Jessie and James attempted to sneak off J's airborne base after rescuing Pikachu, Team Rocket's Meowth and Melodi's Gardevoir. Some of these henchmen were captured by Officer Jenny at the end of their first appearance. The ones that weren't captured appeared in Ill-Will Hunting!. In this episode, the other important henchman appeared, also using a Golbat to fight Pikachu.
These same henchmen also appeared in Pokémon Ranger and the Kidnapped Riolu! Part One and Part Two, where more of their Pokémon appeared. They appeared once more in Pillars of Friendship!, with even more of their Pokémon.
The henchmen made a brief appearance in The Needs of Three! alongside J, after her mission to capture Mesprit, Azelf and Uxie, and were aboard her ship when it was destroyed by the Lake Guardians. Although it is unknown if any of the henchmen were able to get off the ship before it exploded, it is possible that at least some of them perished when the ship flooded—if so, marking one of the rare times that a human is killed in the series.