Welcome to the Space Show

After Pochi Rickman takes the children to the Moon colony, he is attacked and injured by poachers. His injury triggers a report that results in a ban on travel between the Moon and Earth, leaving the children unable to return home. This forces them to journey across the galaxy to Pochi's homeworld Wan in hopes of finding another way back to Earth.

The initial rescue of the injured Pochi establishes early on that the universe holds dangerous threats beyond the children's understanding.

Zughan is a substance derived from a plant related to the wasabi root. In the story's universe, it functions as a powerful recreational drug. Neppo, the host of the universe's most popular entertainment show, seeks Zughan because it serves as a crucial power source for his spaceship Pet Star. With it, he believes he can gain enough energy to become a god-like figure.

Natsuki unknowingly carries Zughan in her bag from the beginning, making the group a target from the moment they leave Earth.

Neppo is the enigmatic host of the universe's most popular entertainment program called The Space Show. He operates from a massive moving spaceship called the Pet Star and pursues the children across the galaxy to obtain the Zughan. His ultimate goal is to become a god by harnessing the power source that Zughan provides.

The threat of Neppo looms throughout the journey, with his henchmen pursuing the children even before he personally appears.

When Neppo's ship arrives at Wan, he uses the Pet Star's tractor beams to steal Natsuki's bag containing the Zughan. In the process, Amane Suzuki is caught in the beam and abducted alongside the bag. She becomes leverage for Neppo to force the other children to comply with his demands.

The tractor beam attack occurs as the children finally reach Wan, believing their journey was nearly over.

At Wan's interstellar festival, the children and their new friends mount a coordinated resistance against Neppo and his forces. Using the teamwork and tricks they've learned throughout their journey, they outwit Neppo's guards, defeat him, and rescue Amane. Their victory prevents Neppo from dominating the universe and saves their friend.

Throughout their journey, the children repeatedly face and evade Neppo's henchmen, gaining experience that prepares them for the final confrontation.

Pochi Rickman is injured by alien poachers who attack him. These same poachers serve Neppo, the main antagonist. After the children rescue the injured dog-like alien from a corn field, Pochi explains he was wounded by these pursuers, setting the chain of events in motion.

The children's decision to help a seemingly injured stray dog leads them directly into a galaxy-wide conflict.

After the Moon colony travel ban leaves them stranded, the children must continue their journey to Pochi's homeworld Wan. Their goal is to reach Wan so they can find an alternative way to return to Earth before their summer vacation ends and their parents come to pick them up.

Pochi's initial promise to take them to the Moon transforms into a longer journey when circumstances change.

During the final confrontation with Neppo at the interstellar festival, the children not only defeat the villain and rescue Amane but also locate and rescue Pyon-Kichi. The rabbit had been kidnapped by Neppo's henchmen earlier in the chase, and his rescue completes their mission.

The class pet's disappearance was the initial inciting incident that started the entire adventure.

Natsuki unknowingly carries Zughan in her bag throughout the journey. The substance was apparently given to her or came into her possession during their adventures. This makes her bag the most valuable prize for Neppo, turning her into a primary target throughout their pursuit across the galaxy.

The Zughan bag becomes the central MacGuffin driving the conflict from the moment Neppo learns the children possess it.

The children return to Earth aboard the Pet Star, the very spaceship that had been pursuing them. After defeating Neppo, they take control of the ship and fly back to their hometown. They arrive at their school just as their parents are arriving to pick them up, completing their summer adventure.

The final transition from pursuit to control of the Pet Star represents the children's growth throughout the journey.