Dennis wears the same Team Rocket uniform as other members, with the black clothes and hat as well as white gloves and shoes with the signature R on his chest. He has blond hair.
At some point before the series, Tony joined and became a member of Team Rocket. When Rusty tried to infiltrate Team Rocket HQ, Tony was called in after Rusty's Bidoof was killed to take out Rusty. However, before he gets the chance to kill Rusty, Pikachu knocks him out cold and steals his gun, firing at Rusty.