While resting at a local towns Pokémon center Ash and co. meet their old friend Duplica, disguised as Nurse Joy (However Brock could see through her disguise (Not literally of course)). Apparently she's in town to attend an acting convention and to have a new Ditto she nicknamed "Mini-Dit" examined. She reveals that the thing that's wrong with it is that, even though it can duplicate other Pokémon, it can't match the size of really tall pokemon like Brock's Onix. Later Team Rocket come up with a plan to steal Mini-Dit, which succeeds. Will Duplica ever find Mini-Dit again? And does Duplica know something about Jessie's Wobbuffet she doesn't?
Duplica enters a double battle with her Ditto and Mini-Dit against Jessie and her Arbok and Wobbuffet.
This is one of very few episodes where Jessie does not wear her lipstick. It happened when she was imitating Duplica when she and James (imitating Ash) were reciting their motto. Another instance like this happened in the Pokemon Chronicles episode "Training Daze" when she and Cassidy (Also not wearing lipstick at the time) were running on the treadmill.
Duplica and Ditto returns for the first time since IL037.
The 'Who's That Pokémon' of the episode is Ninetales.