Having just exited the valley, Yoshino falls ill with a digital world virus and the group takes her to a small cave to rest. Touma and Gaomon force Masaru and Agumon to wait outside the cave because they’re not trained medical professionals like Touma. Inside the cave Touma tells Yoshino to rest as he has yet to figure out what is wrong with her but suspects it is just a lot of stress. He notices that he doesn’t hear Masaru so he leaves the cave and Gaomon tells him Masaru and Agumon ran off. Touma and Gaomon discover them playing in a river while Ikuto and Falcomon enter the cave in which Yoshino is resting. Ikuto grabs hold of Yoshino but the rest of the group shows up to stop Ikuto from hurting her. Yoshino grabs hold of Ikuto to prevent him from attacking Masaru which causes the virus to transmit to Ikuto. Falcomon yells at her for transmitting the virus and Touma realizes that Yoshino isn’t merely stressed out but has a virus.

That night Falcomon tends to Ikuto and hopes that he’ll get better like he did in the past (not sure of what happened in the past yet). In the cave Touma tells Masaru they must get a vaccine for Yoshino because the virus is spreading and she could die. Back in the forest Falcomon has a flashback of Ikuto’s old caretaker, Frigimon, leaving for a place called Wanderer’s Cape to get a cure for Ikuto’s sickness. He decides to go there but first stops at the cave where DATS is staying. Touma examines Ikuto and confirms they have the same virus. Falcomon tells them they must go to Wanderer’s Cape to get the vaccine but they must be careful because Digimon fear it (because humans use to live there).

The next morning the group leaves for the Cape, leaving Raramon behind to watch over Yoshino and Ikuto. During their journey, Masaru asks about where the humans at the cape are but Falcomon says he doesn’t know and that Frigimon might’ve known but humans killed her. They then arrive at the cape.

At his lair, Mercurimon is informed by Gotsumon of the human’s movements but tells Gotsumon to leave the humans alone. Gotsumon runs off angry but is met by Blossomon who wishes to crush the humans just like Gotsumon and the two team up.

The group enters a mansion at the cape and Touma discovers a password protected computer that he tries to crack so that the group can learn more about Masaru’s dad. Masaru, Falcomon, and Agumon leave Touma to investigate the mansion and Agumon comes across the vaccine in a fridge. Blossomon appears and steals the virus from Agumon. Blossomon tells Falcomon that his betrayal has made Mercurimon angry and he attacks Falcomon. Masaru protects him and Falcomon steals the vaccine back from Blossomon. Masaru spots the exit and tells Falcomon to escape with the vaccine. Falcomon questions why Masaru trusts him and Masaru tells him he is a man and men don’t betray their friends. Masaru and Agumon cover for Falcomon and the battle disrupts Touma and destroys the computer he was working on.

Masaru and Agumon are captured by Blossomon but Touma and Gaomon show up. Gaomon evolves into MachGaogamon and frees Masaru and Agumon from Blossomon. Masaru gets his digisoul and evolves Agumon into RiseGreymon. The two Digimon reduce Blossomon back to a digitama.