Hassle in the Castle (Japanese: ズバットのやかた！きけんなめいろ！！ Zubat's Mansion! A Dangerous Maze!!) is the 7th episode of Pokémon: Johto League Champions.
On their way to Ecruteak City, Ash and co. are caught in a rainstorm, but as luck would have it they would find a seemingly abandoned castle. There they meet Dr. Anna and her Pokémon medical team. Brock instantly falls head over heels for her and his Zubat falls for hers. Later Brock and Dr. Anna get trapped in a maze. How will they get out? And Can Ash and Misty do anything about this?
As the heroes continue their journey, a storm approaches and begins to rain heavily. The heroes see they need to get indoors and Pikachu points at a mansion. The heroes knock on the door, but nobody answers. Pikachu pushes the door and opens, so they head inside. The heroes wander a bit and suddenly hear a man screaming. They go after him and open the door and see some people and some Pokémon. A woman approaches them and asks if they have an appointment, to which Brock flirts with her, telling she can call him whatever she wants. The woman is Dr. Anna, whom Brock tries to impress. They soon see a patient having a check-up and Brock realizes the Zubat that was floating around the patient was using Supersonic to check the patient via ultrasound.
Dr. Anna clarifies they use Pokémon for procedures; Machoke massagues people, Spinarak makes bandages and Mareep relaxes the muscles via electricity. Dr. Anna tells the owner of this castle was her patient and when she moved away, she let Dr. Anna set up a clinic. Dr. Anna is about to get back to work, but Brock yells to her not to go, as they have a thing in common - he sends Zubat to prove they both have one. Brock sees they could work together for the good of the people, as a way to appreciate they stay indoors from the storm. Ash tells they might make a good team, but Misty hopes he meant the Zubat. Ash's stomach growls, as now they need to find some food. Team Rocket sneak into the castle and hear a strange sound. They turn back and see a giant shadow, but they realize it was Wobbuffet, so Jessie immediately calls him back. Meowth smells something. They find food and eat it, while Jessie (again) calls Wobbuffet back. They suddenly encounter the twerps, who enter the kitchen.
Brock admits to Dr. Anna he was going to be a Breeder, but after meeting her, he will use Pokémon for medical assistance. Team Rocket pass by him and Anna asks if they have an apointment, causing them to chant their motto. Pikachu goes to electrocute them, but they run through a hall. Anna, Brock and Zubat follow them, as Anna goes to warn them, but it is too late, as they fall down through the floor as a trap. Ash and Misty try to follow them, but the trap closes. Team Rocket are angry, as they are the ones who set up traps. Brock tells as long as Anna is here, he is fine. Anna turns the lights on. Team Rocket are leaving and Anna tries to warn them, but it is too late, as they bash into a wall. Anna tells this is a maze, but has a solution - her Zubat uses Supersonic, revealing on her computer a path out of the maze. Anna tells it is not the whole scan, so Brock's Zubat uses Supersonic, revealing the other part of the map.
Ash and Misty try to find a way in, so Anna's assistant points a location where there is another way in. Anna sees two ways, which are both dangerous. James is scared they can be trapped here for the rest of their lives. Meowth, however, advises to have a lunch break. Anna's assistant led them to the location, but it is overgrown, so Ash rallies the Pokémon to dig out. Anna analyzes the ways, but both are dangerous. Jessie runs out of patience and goes to pick a path, ignoring Brock's warnings. Wobbuffet comes out, pleasing Jessie as he wants to follow her. Jessie goes in, but triggers a trap, causing a wall to appear and hitting her in the head. Anna sees this caused the other way to become safe, while Jessie is annoyed Wobbuffet did not come first. Ash, Misty, Geodude, Pikachu and Anna's assistant dig out the exit, while Pineco and Togepi transport the rocks away.
Anna detects another obstacle, but does not see anything. Jessie and Wobbuffet run, as Jessie replies she knows no danger. She pushes Wobbuffet away, but nothing happens. Jessie sees there is no danger and runs, but triggers a trap, bashing her to the ground. Anna realizes that after triggering the trap the way becomes safe. Ash and Misty remove the rocks and see they are near to excavate the exit. Anna gasps, as she sees her and Brock's Zubat found a way out. Brock imagines he can prove they are as good team as their Zubat and would get married, with Ash, Misty and their Zubat having dresses and tuxedoes and telling them they will have a honey moon. Team Rocket see the Zubat are skilled and Jessie tells this is the exact reason they will steal them. Anna sees the door and thanks the Zubat for leading them here, but Team Rocket steals them and goes to get out, but bash into a door. Misty, Ash and Anna's assistant push, but see they pushed as hard as they can. Pineco uses Selfdestruct and bombs the door, while the Zubat return to Brock and Anna.
Ash and Misty see Anna and Brock are all right. However, Pikachu gets captured, so Ash yells to give back his Pikachu. Wobbuffet yells out, knocking the heroes down, so Team Rocket escape. James sends Weezing, who uses Smokescreen, but the Zubat gust the smoke away. Jessie sends Arbok, who goes to use Poison Sting. However, after being hit by Zubat's Supersonic, it randomly hits Team Rocket instead. For this, Brock's Golbat evolves into a Golbat. Arbok recovers and uses Poison Sting, but Golbat uses Wing Attack to deflect it, then uses Supersonic, confusing Arbok and Weezing, causing them to fall on Team Rocket, who lose Pikachu. Anna sees Golbat became much stronger, causing her computer to be turned off. Pikachu turns around with an evil smile, as he uses Thundershock, blasting Team Rocket off.
At the castle, Anna heals Brock and compliments his Golbat's power. Brock hears it is too strong and thinks it is their love, but Anna tells it is Golbat, crushing his fantasy of getting married. Anna sees he trained Golbat well and tells he will make a fine Breeder, causing him to be deprssed. The heroes wave goodbye to Anna and her assistant, as Ash and Misty pull a heartbroken Brock on their jouney.
- Two of Dr. Anna's male patients were voiced by Eric Stuart and Jimmy Zoppi respectively.
- The "Who's that Pokémon?" is Persian.