Disaster of Disguise (Japanese: 仮面のコーディネーター・ファントム登場！ Masked Coordinator: Enter Phantom!) is the 21st episode of Pokémon: Advanced Challenge.
As the heroes arrive to Verdanturf Town, they meet up with Drew, who cannot participate in the upcoming Contest, since his Roselia has been defeated by the Phantom and his Dusclops. May is surprised and decides to train for the Contest. Just then, the Phantom appears, so Ash challenges him to a battle. However, a woman arrives and starts chasing the Phantom, but fails. In order to find more about the Phantom, the woman requests the heroes to unmask his identity.
Drew is shown to be battling against a dressed man, with his Roselia is losing to a Dusclops. Drew is in trouble, but the masked man claims Drew didn't put much of a fight for a renowned Coordinator. Dusclops uses Shadow Punch, hitting Roselia, followed by Will-O-Wisp, defeating the latter. As the wind blows, the masked man claims Drew would've been even defeated in a Contest battle, then disappears. Meanwhile, the heroes have arrived in Verdanturf Town's Pokémon Center. Max sees Drew giving Poké Balls to Nurse Joy. They are certain Drew is entering the Contest, but Drew denies, for he won't enter this time. May notices Drew's Roselia being quite injured and is told it may not have the strength for tomorrow's Contest. Drew warns them of a masked Coordinator, who calls himself as the Phantom. May goes to train, seeing this Phantom is even stronger than Drew. Jessie asks of Meowth and James to train with her, since Jessie is planning on entering tomorrow's Contest. However, James notices the heroes.
Skitty is sent out and May orders the former to use Blizzard, but Skitty executes the move on them. It stops, making May see there is no need for more training on that move. May decides to throw balls to Skitty, to train her Double Slap by juggling the balls with her tail. Max remembers to win a Contest, the Coordinator must know how to use the attacks, as May remembers Dr. Abby's advice. Skitty succeeds in juggling three balls. May throws some additional balls, but Skitty fails, causing the balls to fall on the ground. As Team Rocket sees their enemies, Jessie is confident she and Dustox will win, while a boy sees them from afar. Skitty tries once more to juggle the balls, succeeding in juggling five balls. Skitty gets excited, but stops juggling the balls and fails. The man who battled Drew, the Phantom, appears to challenge May to a battle, since she will be entering the Contest tomorrow, while Team Rocket observes. Ash goes in to battle with Pikachu, while the Phantom decides the rules are like the Contest's, with a five minute limit. The Phantom sends Dusclops and Ash his Pikachu.
Pikachu starts with Quick Attack, but no damage is dealt due to Dusclops being a Ghost-type Pokémon. Dusclops repeatedly uses Shadow Punch, punching Pikachu with these attacks. The Phantom goes to end a fight, but a car is approaching, so the Phantom calls Dusclops back. The Phantom calls the battle a draw and disappears, with the wind blowing. A woman goes out of the car and chases the Phantom. The Phantom runs off, but gets his hand cut on a branch. Regardless, the woman goes after him, but she trips over and the Phantom vanishes. The woman finds a pencil and is angry, asking loudly what the heroes have done to her son, Timmy. The woman starts shaking Ash and Pikachu, but Brock tells her this is the first time they encountered the Phantom and wonders who Timmy is. The woman begins to tell that Timmy, her only son, stopped going to school, so she hired a detective to look after Timmy. The detective noticed that whenever Timmy went away, the Phantom appeared. The woman is certain the Phantom had lured her son in a dangerous activity.
The woman sees the heroes are trainers and wants them to find the Phantom and discover who he is. Team Rocket sees the shiny rings the woman is wearing and hear the woman would pay a lot for the Phantom to be caught. This amuses Jessie, who thinks she would obtain the woman's shiny rings. The woman takes the heroes to her home, the mansion. As they enter, the boy, Timmy, places a bandage on his hand and goes to take notes about Pikachu, but notices his pen is missing. Timmy approaches his mother, while the heroes introduce themselves. Timmy claims he was in his room, studying and tries to go back. Timmy's mother shows him the pen he lost. Timmy recognizes his pen, making his mother angry, since she found it being dropped by the Phantom. Timmy tries to explain, but Timmy's mother notices the bandage on his right arm, but Timmy goes to his room. Timmy's mother is upset, seeing her son is frightening her.
The woman points out the Phantom also was cut on the right arm and suspects Timmy is the Phantom. They point out Timmy is not as strong as the Phantom looked like. Ash asks is Timmy studying to become a trainer, but this upsets Timmy's mother. She starts shaking Ash, as Timmy is studying to inherit her company, claiming he does not need to be bothered to become a trainer. Brock tells her one can learn much from Pokémon, but Timmy's mother denies that and reminds them they only need to find out who the Phantom is. As the woman leaves, the heroes discuss see Timmy is certainly not happy. Out of nowhere, Timmy's father, Tommy Grimm, appears and confirms Timmy certainly isn't happy. Tommy shows them the costume of the Phantom, explaining Timmy is the Phantom. When Tommy was a Coordinator, he met Mr. Grimm and married her, but she couldn't allow Pokémon to enter the mansion, as she hated them. He made the Phantom costume to participate in the Contests. However, he couldn't hide the secret for too much and has hidden the costume.
One day, however, Timmy encountered a Duskull and brought it home, but his mother did not allow, ordering he should study more. Timmy felt very sad, so Tommy made a new Phantom costume for his son. Thus, Timmy became a Coordinator and gained more confidence. Since Timmy is not allowed to go on a journey, Tommy hopes Timmy has a chance to participate in a Contest. Ash wishes there was something they could do, so Brock has an idea to help him. Timmy, in his room, hopes his mother has not figured out the truth. Tommy and the heroes enter the room. Timmy tries to hide the costume, but is told they are all here to help him enter tomorrow's Contest, which is Timmy's wish. Timmy's mother, Mrs. Grimm is being driven in the car and sees a woman giving her daughter a Poochyena, making Mrs. Grimm think about it. Once Mrs. Grimm comes home, May practices with Skitty, who uses DoubleSlap to juggle the balls.
Suddenly, Brock, dressed as the Phantom, appears and challenges May to battle. Ash, Timmy and Tommy go out of the mansion, surprising Mrs. Grimm, who thought Timmy was the Phantom. However, Brock's mask is nearly taken off, as Team Rocket wants to expose the Phantom for the rewards, promised by Mrs. Grimm. May is not pleased, as their scheme was working fine, but shuts her mouth, as Mrs. Grimm heard that. Jessie sends Seviper and James with Cacnea (who hugs the former) to discover the Phantom's identity. Seviper uses Wrap to bind the Phantom, while James uses his fishing rod to pull the mask, though Brock struggles not to reveal himself. Pikachu is about to use Thunderbolt, but Ash realizes it will hit the Phantom. Cacnea goes to attack the Phantom, but Skitty uses Blizzard, blowing Seviper, Cacnea and Brock away. However, Brock falls down and, by accident, his identity is revealed, so he pulls his mask again. As Cacnea and Seviper are falling to the balloon, Pikachu uses Thunderbolt, blasting them and Team Rocket off.
The Phantom leaves, surprising Mrs. Grimm, while Ash, Max and May claim the Phantom got away once more. Tommy knows his wife did see Brock's face. Surprisingly to Tommy, Mrs. Grimm claims Timmy is not the Phantom and leaves to her office. Timmy surely knows that he'll enter the Contest, while May knows she'll enter, too. This makes it certain May and Timmy will battle each other and neither side will back down.
- Featured Pokémon: Crawdaunt, Chinchou, Houndour, Volbeat.
- The title is a reference to the 2002 comedy film "The Master Of Disguise".