Ash and his friends stop at an air station to get a closer look at the Leviathan 2, a luxury dirigible taking passengers on a flight around the world. The ship has landed to refuel and the crew needs medical assistance for some passengers' Pokémon, so Brock volunteers to help. The passengers are two wealthy young ladies, Madison and Alexa, whose two Kecleon are suffering from a little airsickness. Brock's remedies make sure the Kecleon, called Greenie and Reddie, are back to normal in no time flat.
Greenie and Reddie are taken back to their stateroom, which Team Rocket then tries to rob of valuables. Greenie snatches a jewelry box back from Team Rocket and the Kecleon flee the room. As reports come in that the Kecleon are running around the ship, our heroes pitch in to help find them—Team Rocket is on the trail too, hoping to get their hands on that jewelry box. The chase leads everyone out of the dirigible, into the air station terminal, and then right back out again.
As Greenie and Reddie exit the terminal, they're surrounded by our heroes and the dirigible's crew. Team Rocket catches up to everyone and tries to grab them. Now it's clear that Greenie and Reddie weren't being mischievous, they were trying to keep the jewelry away from Team Rocket! Their owners join Ash in battling Team Rocket and soon Team Rocket goes blasting off, the jewelry box is recovered, and the dirigible can finish refueling and leave.