A small Digimon is being chased by a larger Digimon in the Digital World. Just before the small Digimon is attacked by the large Digimon, another Digimon slams into the side of the attacking Digimon. Suddenly, a large explosion sends the small Digimon into the real world. In the next scene Takato is playing Digimon cards with his friend Kazu. Takato beats his friend, and after Kazu runs off Takato notices a blue card in his collection. He runs it through his Card Reader before rushing off to school. Because he is late, he is forced to wait in the hallway. In this time he doodles a Digimon which he calls Guilmon. After school he sees that a storm is coming and runs to get his Digimon cards. Once there, he realizes that his Card Reader had become a Digivice. He runs home, thinking of ideas as to why this happened. Finally, he comes to the conclusion that he must be a Digimon Tamer. In the morning, Takato notices a DigiEgg in the Digivice, and also that it has hatched. The Digivice leads him to a construction site, where he finds Guilmon. At first Takato is afraid because Guilmon blasts a nearby rat without any thought, but Guilmon convinces Takato that he won’t hurt him.

Takato is ecstatic over Guilmon, but he does not know what to do with him. So, he tries to hide him in a box, but his parents are still suspicious, thinking Takato is trying to sneak a pet into the house. However, they do not pursue their suspicions and let him take Guilmon up to his room. The next day, Takato hides Guilmon in an alley before going to school, keeping him occupied with bread and telling Guilmon that he’ll play with him after school. However, Guilmon becomes bored and tries to surprise Takato at school, but instead surprises the principal. When the principal sets off the fire alarm, Guilmon flees to the cafeteria where he enjoys a nice snack. While trying to find Guilmon, Takato runs into Henry and Terriermon. Terriermon makes a joke about Takato being a bad trainer, and so Takato gets upset and runs away. However, it doesn’t take long for him to find Guilmon, and there is a happy reunion. Takato then decides that they will have to find a better hiding place for Guilmon. They go to the park to search, but are surprised by Rika and Renamon’s attack. While Takato does not want to lose Guilmon in his first ever fight, he is taken aback by the fact that he is fighting the girl from his dream.

As Guilmon and Renamon try to fight each with little success, Rika tries to get information on Guilmon. When none is available, she decides to modify Renamon with a cannon arm, which would easily obliterate Guilmon. Takato pleads with Guilmon to stop fighting, and when he listens Renamon misses. While Renamon is trying to aim the cannon, Henry and Terriermon arrive and are able to stop Rika and Renamon. Henry tells Rika that Digimon are not just tools for fighting, but she won’t listen, and instead walks away with Renamon. This causes Henry and Takato to introduce themselves as they walk towards Guilmon’s hiding spot, a shed in the park. Takato runs into Jeri at his parents’ bakery, and she tells him that she will not rat him out for skipping school. Then, Henry makes Terriermon promise not to digivolve, while Rika wonders why Renamon can’t digivolve. Even when she is recognized as “The Digimon Queen” she is doubtful that she is competent enough to be a tamer. After Takato has an epiphany about modify cards, he disguises Guilmon as a man in a Guilmon costume. Everything is fine until Guilmon smells Renamon, and after following the scent comes upon Rika and Renamon. Once again, Rika challenges Takato, and they begin to fight. Henry shows up in the middle of the fight to break it up, and sends in Terriermon to Guilmon’s aid. However, in the midst of the action Terriermon digivolves into Gargomon, and begins firing in every direction, unable to control his powers. Gargomon aims at Rika, ready to obliterate her, when suddenly Guilmon takes him out from the side at the last second. Riku is now afraid, wondering if digivolving really is such a good idea.

Hopeless, Takato and Henry have Gargomon stand on his head, hoping that maybe it will make him de-digivolve. Henry goes to bed, dreaming of a time when he was playing his Digimon computer game and Terriermon encountering Gorillamon. When he wakes up he sees that Terriermon is back to his normal self, apologetic and tired. After Takato sketches Guilmon’s Champion form, he and Henry walk downtown, when they suddenly notice that a digital field is following them. It turns out to be Gorillamon, and it will not return unless it fights Terriermon. This triggers memories of Henry playing his Digimon computer game, unable to stop Terriermon from digivolving on the game. After remembering how he was able to obtain Terriermon in real life along with his realization that Digimon are real, he suddenly has a stroke of brilliance. Henry pulls out the Training Grips card, the card given to Takato by Kazu. He flings these at Gorillamon, and while he’s caught of guard they attack and defeat the Digimon. However, Henry makes sure that Terriermon does not absorb the data of Gorillamon. Takato decides that he and Guilmon make a good team, while Henry and Terriermon do as well.

Takato goes off to school the next day, and sees all the students huddled around the playground. It seems that something has drawn many odd-shaped chalk lines around the playing field. While most of the children lump this with the dragon sighting (Episode 2) Jeri claims to have seen the monster behind the act. Jeri says that while she was in the infirmary, she opened a cabinet and saw the creature there (the creature being Calumon). Then the episode changes to Calumon’s perspective, and Calumon sees people playing soccer. When they leave, he wants them to return, so he redraws the chalk lines, inventing new rules as he goes. In the morning, Takato and Guilmon happen upon Calumon while Takato feeds the school rabbits. After waking up, Calumon proceeds to play soccer like crazy. Takato and Guilmon debate who Calumon’s trainer should be, ruling out Kazu for his poor strategies (strong offense but no defense), Suzie for her immaturity, and Jeri for no particular reason. Later, Calumon convinces Guilmon to leave the shed in the park and play with him on the field. Takato finds the shed empty, but is startled to see what appears to be a digital field appearing over the playing field. Together, Henry, Takato, and Rika are able to defeat the Digimon (Vilemon) and Rika has Renamon absorb the data.

In the beginning of the episode, we finally learn something about Rika’s home life when it’s Parent Day at her school (a private school). Her mother attends, but has to leave early on account of an emergency photo shoot. Rika is taken out of this flashback by a Digimon coming through a digital field. Rika tries to fight off this powerful Digimon (Allomon) but it is clear that she is outmatched. However, she refuses to let Henry and Takato help, claiming that she can do it on her own. After some quick thinking and some modify cards, she finally defeats Allomon, and tells the boys again that she doesn’t need their help. In the night, Rika has a memory of winning the Digimon Battle Card Tournament. After winning, many Digimon come to her, wanting her to be their trainer. She only wants the strongest Rookie, and Renamon steps forward. This is how they became partners. In the night, a Digimon appears and Renamon and Rika go to the scene. The Digimon, Dokugumon, is very strong, and they are overwhelmed and caught in a web. Renamon frees Rika, and tells her to run away, but Rika is unable to because she is too attached to Renamon. It is then that Renamon is able to digivolve into Kyubimon, and they make quick work of Dokugumon. Kyubimon explains to Rika that only her affection could make Renamon digivolve.

The episode starts with Rika being unsure of whether or not Digimon are real. She thinks that maybe Digimon are data with feelings, or even that Digimon are not data at all, but real things. Either way she begins to realize that they may not be just fighting machines. In the morning, when Takato visits Guilmon, Guilmon tells Takato that he dreamt he was disappearing. Oddly enough, he really does begin to disappear, and Takato freaks out and goes to see Henry. Henry theorizes that Guilmon is probably starting to return to the Digital World, and that there is nothing they can do to stop it. After school, Takato goes to the park and sees Guilmon playing with Calumon. He asks Calumon if he is lonely and if he has a home, but he says no to both. Calumon leaves and Takato takes Guilmon to look for Calumon, but runs into Rika and Renamon instead. Rika demands a fight at first, but then decides against it and invites them to her house. She tells him about her dream (involving Lynxmon and Renamon). Afterward, Takato tells her about Guilmon disappearing, and she says that it is no big deal. Takato is very surprised to learn that Rika still considers Digimon purely as data. As Takato and Guilmon walk home, Giulmon begins to disappear, only much faster then he did before. Takato worriedly calls Henry to come, and together they seek out Rika. When Terriermon and Renamon begin to disappear as well, they think it might be coming from the tunnel close by. So, they go in the tunnel, and see a big bubble surrounding the area. A place opens up for them to go inside, and they find Guilmon. Guilmon makes it possible for everyone to escape, and they make it out just as the field is erased.

Takato starts to design Growlmon- what he thinks should be Guilmon’s Champion form. Later that night, Impmon causes trouble in the park before noticing that Guilmon is locked in the shed. He demands some of Guimon’s food, and belittles Guilmon for being “A Digipet.” The next day the class has a discussion about who is the person behind the mischief in the park. Takato and Henry decide that it could not possibly be Guilmon, but they still need to be careful because teachers are starting to patrol the park. However, this doesn’t deter Takato, who goes to the park that night to feed Guilmon. Takato pleads with Guilmon not to leave the shed, and then is stopped on his way home by a cop. Takato’s teacher, Ms. Isaji, makes up an excuse for him and then escorts him home. As soon as Ms. Isaji leaves Takato runs to the shed, which he finds empty, and he immediately assumes that Guilmon really is the culprit. When Guilmon returns, Takato loses his temper, telling Guilmon off before running home. The next night, a powerful Digimon (Devidramon) breaks through and begins attacking Guilmon. Guilmon refuses to fight back, even when Terriermon and Renamon show up to fight as well. Only when Takato finds out who was really the culprit and forgives Guilmon does Guilmon start attacking, eventually digivolving into Growlmon. Growlmon easily defeats Devidramon, and scares off Calumon in the process.

Face to face with this huge Digimon, Takato fears for his life. However, Growlmon begins crying and tells Takato not to be afraid, even begging to be Guilmon again. Takato tries to get Growlmon to fit in the shed, but Growlmon gets stuck. This makes Takato realize that he has to get Growlmon to de-digivolve. His first attempt is to swipe the digivolve card backwards, but that doesn’t work. Next, he tries to work any excess data out of the Digimon, and even exercises alongside him at one point, but that doesn’t work either. His last resort is to leave Growlmon overnight and hope that he changes back, although he knows that it is unlikely. In the night, Takato finds Growlmon and Calumon outside his window. Worried, Takato calls Henry and they decide to leave Growlmon in the tunnel where Guilmon had begun to disappear before. However, Impmon stumbles upon Growlmon in the tunnel and chases him out. Exhausted, Growlmon collapses on the playground, and Takato finds him there the next day. Takato’s last resort is to camouflage Growlmon using green and brown paint. Rika shows up and tells them it won’t work, having Renamon find Growlmon in an instant. Soon after, it begins to rain, washing the paint off Growlmon. When Takato starts to cry, claiming that he can never do anything right. When the storm ends, a rainbow appears, and Growlmon returns to Guilmon.

While Rika is walking home, Calumon runs up to her at the same time as Rika’s mother does. Rika’s mother makes a big deal about the cure little Calumon, embarrassing Rika. As soon as Rika makes it home, Rika tells Calumon off, who leaves, crying. Renamon wonders how shoe could become closer to Rika. Rika is then kidnapped by IceDevimon, who asks Rika to be his Tamer. Rika refuses and calls for Renamon, who starts to come to her aid, but then decides against it. Takato and Henry hear Rika’s screams and come to the scene, but Guilmon and Terriermon are immediately frozen by IceDevimon. After countless attempts to break their Digimon out of the ice, Henry and Takato are helpless. Finally Renamon shows up, but she is no match for the powerful IceDevimon. Rika tells Renamon that she cares for her as a friend, and Calumon cheers up. With Calumon’s help, Renamon digivolves to Kyubimon, but even with the new strength is unable to defeat IceDevimon. Henry then uses an expansion card on Terriermon, who grows very large and busts out of the ice. When Guilmon is freed also, Henry uses a card combo on IceDevimon, and defeats him easily. After this experience, Rika declares that she hates Digimon.

Rika, upset, throws everything Digimon-related away. Then, in an unbelievable upset, Takato manages to defeat Kazu at the Digimon Card game. Bragging, he tells Kazu how he has real-life experience. When a digital field appears, Henry and Terriermon investigate. However, Henry forbids Terriermon to fight, and has to pull Terriermon away when he tries to fight anyway. It turns out that there was no need to fight though, because Yamaki uses Yuggoth to defeat the field. While Henry is trying to tell Terriermon the reason he is not allowed to fight, Suzie comes by and begins to play with the now inanimate Terriermon. Meanwhile, Renamon finds Henry and tells him that she wants to be friends with Rika. However, when Henry asks why they were chosen to be Tamers for the Digimon that they were given, Renamon had no answer. At school, Kazu easily defeats Takato at the card game. Takato gets upset, claiming that he has real-life experience and that he deserved to win. He gets so upset that he shows Kazu and Guilmon, who sneezes and scares Kazu away. Guilmon then senses that Musyamon is close by again. So, Henry and Takato find him and begin to fight. Takato swipes card after card, but nothing is working against Musyamon. Finally, Henry allows Terriermon to fight and he Digivolves to Gargomon. Gargomon defeats Musyamon, and then Henry apologizes to Gargomon for not letting him fight. Takato then apologizes to Guilmon for swiping so many cards.