Zack runs into the book store which Yume and Maxwell are in charge of. Yume, who is friends with Zack from school, allows him to quickly read some manga books (as it is not available at his convenience store). Zack thanks her wholeheartedly, and enjoys the manga, laughing rather noisily, as Yume works on her story-writing with Maxwell.
That night, Yume continues to write her personal stories, which involve herself and Maxwell as the protagonists on various fictional adventures. Maxwell shares the adventure stories about himself and Yume with the Ham-Hams each day at the clubhouse. Enjoying them so much with Yume stopping at cliffhangers, Maxwell invites everyone to the shop when she continues her stories.
The next day at school, Zack notices Yume writing alone on the stairwell; he is curious about what his friend is writing and notices that she looks lonely. He asks her about it, but she is shy about sharing it. Zack then takes Yume's book, as he wants to read her stories. When he sees that she is writing self-oriented stories about herself and Maxwell as fictional heroes in space, he finds it funny and playfully teases her (though he doesn’t mean to hurt her feelings). Upset by this, Yume shouts angrily at Zack as she runs past Laura andKana talking to some friends. Zack is shocked, as he did not expect that she would react this way, and he wasn’t able to give her book back to her because she ran away from him. He keeps the book to return to her later, feeling bad about what he had said to her.
At the end of the day, Yume gets home, and Maxwell and the Ham-Hams are unaware of what has happened at school. She sits by her bed crying, and as Maxwell tries to comfort her from his cage, she says that she will stop writing her stories, much to the Ham-Hams’ dismay. She is now worried that her stories about herself and Maxwell are silly, and that people will laugh at her if they read them.
Leaving the store, Maxwell apologizes to the Ham-Hams about what has happened. Just as they were about to part their ways, Howdy notices Zack with Laura andKana. Zack had been trying to find Yume to apologize about what had happened. He admits that he didn’t want to hurt Yume’s feelings and intended to return the book to her after she ran away, but had unintentionally lost the book, and feels terrible about the situation. He wants to apologize to Yume, but is worried because he can’t find her book and doesn’t know what happened to it. Laura and Kana understand, and try to help him find the book.
The Ham-Hams overhear Zack confessing what he has done to unintentionally upset Yume and accidentally lose her book. Enraged by this, Maxwell completely loses his temper and says that he would never forgive Zack. This offends Howdy, as he knows Zack didn’t mean to upset Yume or lose her book. This causes the two to fight.
Maxwell decides to stay with his owner for a while, until she recovers from her sadness.
The next day, Howdy is at the clubhouse with Boss, Bijou, Hamtaro and Dexter. Maxwell, however, has not turned up. Howdy feels sad about the fight with Maxwell; he also knows that Zack feels bad as well, and that he isn’t a bad kid. Zack had been desperately trying all night to find Yume’s mysteriously lost book, and didn’t get any sleep. They soon head outside and wait for Maxwell. Just as Bijou figures Maxwell will not be not arriving, he suddenly appears over the horizon, cheerful as can be. Howdy immediately runs up to him to apologize, and Maxwell apologizes deeply to Howdy as well, saying that he is very sorry for saying such things about Zack, admitting that it was his mistake in starting the fight in the first place. The two friends happily forgive each other.
Zack, meanwhile, runs through the park, still searching for Yume's book; he skips class, dedicated to finding the book for his friend Yume. He had recently remembered that he had tripped and accidentally dropped it near an alleyway, and believes a flock of thieving crows had stolen it (which turns out to be true). The Ham-Hams climb up to a crow nest, find the book stored there, and glide down with it. They return it to Zack, dropping it on his head, and he is elated to find it. He immediately returns it to Yume along with Laura andKana, and apologizes to her. Yume forgives him with a smile, restoring their friendship, and Zack is bashful.
Together, Laura, Kana, and Zack all contribute to help Yume write and illustrate fantasy stories about all of the Ham-Hams. Yume then shares the stories with everyone at school, which turns out to be a success, and she gains a good friendship with Zack.