Tai asks Agumon why he doesn't just stay in his Greymon form because he thought it was really cool. Agumon tells him that he can't because it uses too much energy. Suddenly, a Monochromon comes out of nowhere and attacks. Then another one appears! The DigiDestined run away as the two Digimon fight. When the sun begins to set, the group realizes that they are tired. Matt wants to keep walking because they don't know if it's safe to stop, but Tai says they need food. Tentomon finds a lake for them to camp at. They find an empty trolley car there and decide to stay in it. Now that they have shelter, the group just needs food. The kids and their partners all go to gather things to eat for dinner. Tai starts to realize that Matt doesn't really treat T.K. like a brother. It's much more like he's a bother. Sora agrees with him. As Joe looks in the sky to figure out where they are, he finds that he doesn't recognize any constellations. He can't even find the north star. Tai suggests that they could be in the southern hemisphere.
Everyone is getting very tired and are ready to go to sleep but Izzy thinks that they should take turns standing guard. Tai says that they can all do it for an hour but Matt says T.K. is too young and needs sleep. He then starts to get in a fight with Tai for bothering Gabumon. Joe finally decides that the order will be Tai, Matt, Izzy, and Joe. Everyone else can go sleep in the trolley. While they're sleeping, Matt has Gabumon go sleep be T.K. to keep him warm.
During his turn, Tai notices that Matt is up too. Matt apologizes and says that it's stressful being in the Digital World and watching T.K. Tai asks if they even live in the same house and Matt explains that their parents are divorced and he lives with their dad while T.K. is with their mom. After Tai says that that explains a lot, Matt runs away to a nearby island. Then Tai and Agumon hear Matt playing his harmonica. Gabumon hears it too and comes to join his partner.
While Tai and Agumon are sitting by the fire, it begins to spark and the ground shakes. The sparks have hit a Seadramon and he's mad. He pulls away the island everyone else is on leaving just Matt and Gabumon on their separate one. The digimon try to fight Seadramon but are not strong enough. Agumon also doesn't have the strength to Digivolve. Matt and Gabumon have now jumped in the water to distract Seadramon but he grabs Matt. As he is in trouble his Digivice begins to glow and Gabumon digivolves to Garurumon! Garurumon frees Matt and defeats Seadramon. Gomamon has his fish friends bring the island back to main land.
The DigiDestined then discover that their digimon can only digivolve when they are in trouble like how Matt was in trouble or when Tai was and Agumon digivolved. Everyone is very tired after an exiting night and all fall asleep except for Matt and Tai. Tai hears Matt's harmonica again and sees him playing for his sleeping brother and their partners. Tai watches as Matt plays and T.K. sleeps with a smile on his face.