On their way to the next island Ash and co. meet a Nurse Joy who was "more buff" than the other Nurse Joys they met so far in Misty's opinion. She explains that because the group of islands are so small they don't have Pokémon Centers, so she goes from island to island to help heal the hurt Pokémon. Inspired by this, Tracey makes a new sketch called "Nurse Joy: The Pokémon's Florence Nightengale". When helping a herd of baby Seel Team Rocket appears to capture them. After calling for help, the giant Magikarp that Nurse Joy saved years ago not only answered the call, but evolved into Gyarados and help them beat Team Rocket.
The Nurse Joy in this episode was different from all others in certain physical aspects:
She is more active going from island to island giving her a more toned physique.
She is also tanner but she has been since she was a child because of the island sun.
She was strong enough to throw a giant Magikarp into the bay.
Tracey makes a reference to Florence Nightengale, a nurse who served in the Crimean War helping injured soldiers on the field.
Nurse Joy said she was treating a sick Cloyster, but when we see her underwater, she is actually treating a Shellder.
James didn't seem to recognize the Magikarp that attacked him, but he had previously owned one and has been riding around in a Magikarp shaped submarine since coming to the Orange Islands.
Despite being giant, the Gyrados that Nurse Joy's Magikarp evolved into did not appear to be any larger than a regular Gyrados.
The "Who's that Pokémon?" in this episode is geodude.
"I'll call this piece "Nurse Joy: The Pokémon's Florence Nightengale."
~Tracey drawing a sketch of the Nurse Joy they met.