As the kids come to terms with being stuck on an island in the middle of nowhere, a brave Digimon by the name of Leomon, who is also on Infinite Mountain, is attacked by his arch-rival, Ogremon. However, the fight is soon broken up by Devimon, one of the most evil Digimon off all. He informs them of the DigiDestined’s presence on the mountain, and orders them to work together to eliminate them. Whilst Ogremon’s only objection is to working with Leomon, Leomon is completely against the idea, and attempts to strike Devimon, who strikes Leomon in response, taking control of him in the process. Meanwhile, Tai is attempting to draw a map of the island, despite the comments of the other kids on his poor map making skills. At that moment, Leomon appears and, much to the surprise of the other Digimon, proceeds to destroy the group. Whilst making their escape, Tai drops his map. He goes back for it, and Agumon fires a Pepper Breath to defend him, which ends up burning the map. Soon, the way is blocked by Ogremon, and the group are left with no choice but to stand and fight. The Digimon change to their Champion form, and manage to hold off the enemy until Devimon causes a landslide above, distracting them and giving Ogremon and Leomon the chance to retreat. Once the dust settles, the kids find their Digimon back in their Rookie forms, tired and hungry.
Whilst searching for a decent place to rest, they come across a mansion, of all things, and decide to investigate. They discover a feast laid out in the dining room, and are soon helping themselves. As the sun goes down, the kids and their Digimon have a relaxing bath before settling down in bed. Everyone quickly falls asleep, allowing Devimon and his two servants to sneak into the mansion unnoticed. However, Tai and Agumon are soon making their way to the bathroom. As they’re about to head back to bed, Ogremon jumps out from hiding, and they hurry to escape, before running into Leomon. At that point, Devimon reveals himself to Tai and Agumon, and the mansion turns out to be an illusion. As the rest of the group awaken to this reality, Devimon proceeds to eliminate them, raising their beds into the air. At the same time, the island begins to be torn apart by Devimon’s Black Gears. Agumon soon realises that he doesn’t have the strength to fight against Leomon, having eaten no real food at all, and Tai is soon in Leomon’s grip. Tai’s bed then crashes nearby, and his digivice falls out, shining a bright light that frees Leomon of Devimon’s control. Leomon then fires a blow at Devimon, distracting him from the other kids, who are sent flying off in all directions. But before Leomon can attack again, Ogremon appears, and so he’s left with no choice but to send Tai and Agumon away, as he is once again taken over by Devimon. Now the kids are separated, and the island continues to drift further and further apart.