Tama is infected with a dangerous computer virus and it is up to the Yorozuya to save her. To do so, they must enter her body and go on a fantastic voyage.
In a normal morning in Kabuki-chou, Tama is hard at work cleaning up Otose's bar. Otose greets her after waking and freshening up. She complements Tama on being a hard working employee unlike Catherine but admits that she was better off sleeping in, since the bar opens at nights. Tama responds that extra sleep doesn't effect a robot like her so no worries. Otose counters that sleep is good for the body and mind no matter if they were human or robot and they have to maintain that stability or become a good for nothing like Gintoki who gets sick all the time. Tama remarks that robots don't catch colds but Otose worries that she might be sick since she was working in the bar nonstop. Tama again tells the elderly woman that she was fine, being the happiest as he works with Otose. She finally turns to look at her horrified employer, revealing that her image has degraded to that of a 16-bit figure.
Few hours later, Otose tells her experience with Tama's appearance to the Yorozuya, who don't believe her. That is until Tama returns from her supermarket trip... now looking like an 8-bit character complete with Dragon Quest -style speech text and mannerisms. Everyone grows concerned with Tama's well being, except for the apathetic Gintoki, whose bias for 8-bit gaming shows as he believes she is fine. Shinpachi and Kagura demands he fixes her and he pretends to do so utilizing an 8-bit scene. The Yorozuya decides to take Tama to Gengai's shop and the old mechanic gives his diagnosis: she's infected with a computer virus, called Tapir. Self-replicating and self-evolving, it embeds itself deeper into its host and consume the host entirely. Its strength depends on the type of program it consumes and since Tama is an advanced robot, Tapir had become a very powerful and dangerous threat. To make matters worse, Tama has been infected for a while so by the time Gengai creates an vaccine, Tama would already be "dead". He admits that there's another way to save her, and Gintoki demands that the mechanic tell them, not caring that this way may put the Yorozuya and Tama in danger. Instead of telling the trio, Gengai chooses to show them... by shrinking them through a mallet strike and placing them inside Tama to destroy the virus directly.
Gintoki, Shinpachi, and Kagura are given toothpicks, placed in a dirty bowl and are thrown into Tama's mouth. The group paddle through her oil-rich stomach, complaining about going in blind along the way. They reach the shore leading to the entrance to her small intestine and encounter an injured man in a white bodysuit, an arrow up his behind. The figure, with his last breath, asks them to tell the king that the white blood cell army has fallen to the Tapir and begs the leader to flee. He should also search for the three legendary midget heroes from another world (heavily implied to be the Yorozuya).
- Various parodies of certain scenes from Final Fantasy appear in Gintoki's flashback,among one of them is where Aerith Gainsborough killed by Sephiroth in Final Fantasy VII.