The DigiDestined and their partners are all very tired from wandering around and Izzy's laptop still won't work. Tai tries hitting it and Izzy gets mad. Tai sees smoke in the distance and he and Agumon go to see what it is. Izzy finally gets his computer working but unfortunately, the battery is low. Tai calls everyone else over and they see the smoke is from a factory. The kids go to investigate it but find the factory to be abandoned. There are however lots of machines putting things together by themselves. Everyone splits up into two groups. The group of Tai, Agumon, Sora, Biyomon, Joe, and Gomamon find an Andromon stuck under a machine. They are able to free him but at the same time, a Black Gear gets stuck in his leg. He wakes up and begins to attack. Agumon blasts the roof above Andromon and it collapses on top of him. The group then runs away. Meanwhile, Izzy, Tentomon, Matt, Gabumon, Mimi, Palmon, T.K., and Patamon find a giant battery that powers the whole factory. Izzy tries to figure out how it works as the others watch the machines. Izzy and Tentomon find a way inside the battery which is full of codes. Izzy erases some of it and the factory looses all of its power. When Izzy rewrites the code in, the power comes back.
Meanwhile, Andromon has gotten free and is chasing Tai's group.Izzy is still trying to decode the inscriptions in the battery. Tentomon wonders why Izzy would rather spend time with puzzles than with people. Izzy says it's because he things it fun to try and figure things out. He wants to know how they all got to the Digital World and what the Digimon are. Tentomon says he still doesn't understand Izzy and asks if there is a deep dark secret he's hiding. Izzy remembers a conversation that he overheard his parents having. Suddenly, the text on Izzy's computer starts to jumble and his Digivice starts to glow. The machines that Matt's group are watching start to take the things they are building apart. Izzy has unlocked something on his computer but Tentomon starts burning and glowing. Izzy disconnects the program and Tentomon gets better. Andromon is about to get Tai's group when Tai grabs him with a crane and he is stuck as they run away.
Everyone comes back together but Andromon has gotten free and finds them. He shoots missiles that are about to hit T.K. but Garurumon saves him. Then the missiles aim for everyone else and Greymon joins Garurumon. Unfortunately, the two champions can't beat the ultimate. Then Izzy putts the program back into his computer and Tentomon Digivolves to Kabuterimon. Kabuterimon destroys the black gear by aiming for Andromon's right leg and Andromon becomes good again. Then he helps the kids get out of the factory by going through the sewers.