Ash and his friends arrive in a new city filled with skyscrapers, HopHopHop Town. As they are walking the streets, a woman runs up, calling for her son, Arnold, and embracing Ash by mistake. Once Ash clears up the misunderstanding, the crew learns that the woman's son, Arnold, as well as many other children have all disappeared. Officer Jenny pulls up to add another missing child poster, and Brock immediately volunteers to help solve the mystery. Ash is reminded of his own mother and takes it upon himself to solve the mystery. It turns out the children have all been missing for the past three days. The crew arrive at the Pokémon Center, and begin asking around. Nurse Joy then reveals another mystery. The Pokémon in the center have all lost their energy as of three days ago. Suddenly, a device on Officer Jenny of HopHopHop Town hip starts beeping. Jenny explains that she is tracking sleep waves that have been appearing in the city. Meanwhile, Team Rocket is also tracking the source of the sleep waves. They have arrived at this city, and they are plotting to snatch the source in order to put the Boss to sleep. While he is asleep, they plan to take a vacation. The scene ends as they all weep about not having had a vacation in so long. Ash and group track the sleep waves to the roof of an enormous skyscraper. As they step off the elevator, they discover a huge mansion at the end of a trimmed walkway. Ash takes initiative and he and Brock burst through the door. To their surprise, there is a formal gathering of well dressed adults, and a podium on which rest Drowzee and Hypno. The adults explain that their old Drowzee finally evolved to Hypno three days ago, and they have been using Hypno's sleep waves instead of sleeping pills. Finally, a man explains that they are the members of the Pokémon Lover's Club, who have all grown to love Hypno the most. They had been working hard so that their Drowzee would evolve. Apparently, the city life is stressful on the members, and so they have turned into insomniacs. The only cure they could find was Hypno's sleep waves. However, as Brock deduces, Hypno's hypnosis is generally used on Pokémon. When altered to affect people, it has side affects that cause Pokémon to lose energy, and possibly affect extra sensitive kids. Misty, curious as to this last idea, allows herself to be hypnotized by Hypno. Hypno starts its Hypnosis and she suddenly begins acting like a Seel, and runs out of the mansion, and into the park surrounding the mansion. It opens up into a clearing revealing not only Misty, but all the missing children, acting like Pokémon. Brock explains that the affliction, "Pokémonitis," caused by Hypno's waves, is causing all the children to believe they are Pokémon. Officer Jenny attempts to awaken the children from their hypnosis, but it is of no use. The head of the club suggests using Drowzee's sleep attacks to induce dream wavelengths to counteract Hypno's wavelengths. Back in the mansion, Drowzee uses its ability to put Misty into a trance. Finally, it claps, awakening Misty from both the trance, and the hypnosis. Relieved that this solution worked, Ash carries Drowzee back to the clearing to cure the other children. En route, Team Rocket soars down from the sky on hang gliders, reciting the motto, with a snappy, "Meowth, that's flight!" On the ground, Jessie pulls out a mirror, and they try to get Hypno to hypnotize itself. Ash, with some fast thinking, throws a potted plant, smashing the mirror. Not yet finished, Team Rocket breaks out the whips and snares Drowzee and Hypno. When asked why they didn't start off with this strategy Jessie remarks, "We have to fill the half hour." Ash holds onto Drowzee while Misty cuts the whips with Staryu. Ash calls Pidgeotto to gust Team Rocket away. With the Rockets out of the way, they use Drowzee to cure the children, who awaken, and run home. Also the woman from the beginning runs up and embraces her son as well. They head back to the Pokémon Center and cure the Pokémon there. Misty wonders what they dream about. Brock suspects they dream of getting stronger and evolving. Nurse Joy then sighs that Psyduck is still holding its head. Brock, as a Pokémon Breeder, volunteers to take it, but shortly after heading out, attempts to foist it off on Misty, claiming that as a Water-type Pokémon, it should go to her. Misty does not want such a boring Pokémon, and refuses. Ash's Pokédex reports that Psyduck always has a headache, and Misty, in a fit of shock trips over a rock and a Poké Ball rolls out of her bag in front of the unfortunate Pokémon. Psyduck pecks the Ball, and is caught, much to Misty's dismay.