The Tower of Terror (Japanese: ポケモンタワーでゲットだぜ！ Capture at the Pokémon Tower! ) is the 23rd episode of Pokémon: Indigo League.
Ash, Misty, and Brock are heading to Lavender Town so Ash can catch a Ghost Type Pokémon to win against the gym leader, Sabrina. As they are walking, the fog becomes thick and hard to see. Brock says everyone should hold hands so no one gets lost. Brock accidentally grabs Pikachu's tail instead of Ash's hand, resulting in him getting shocked. Misty screamed in terror only to realize it was Brock getting shocked. Then Ash turned around with a skull mask on and Misty, Brock, and Pikachu were scared. Ash then took off the mask and explained that in order to catch Ghost Pokémon they must confront their fear. Misty, Brock, and Pikachu scolded Ash for playing such a dirty trick as to scare them and Ash got shocked by Pikachu as punishment. Misty then berated for his "Bone headed jokes", Ash then quipping that he "should have saved the mask until for next year's Halloween".
They arrive in Lavender Town and they go to the Pokemon Tower. Everyone except Ash is too scared to go in and they want to wait until morning. Meanwhile, Team Rocket watches them from a window inside the tower. James runs off and he falls through a hole in the floor. Jessie and Meowth look down and see James lying on the floor and asking him if he is alright, but Meowth notices a closet is opening, a Gastly pops out of it and scares Meowth. Jessie asks him what's wrong and Meowth points to the closet, but the Gastly disappears before Jessie sees it. The Gastly goes behind Jessie and starts mimicking her. Meowth uses Scratch to attack it, but misses and scratches Jessie instead. Jessie whacks Meowth with a frying pan and Meowth falls down the hole James fell into earlier. Jessie looks into a mirror and sees the Gastly behind her. It frightens her so much that she falls down into the hole with the others. The weight of the three of them opens up a new hole and they fall down it. Their screams are so loud that Ash and his friends can hear them. Team Rocket gets back up, but Gastly scares them again, knocking them out.
Outside, Ash and his friends decide to go in. Misty and Brock are scared and they tell Ash to go in first. They enter the tower and the doors close by themselves, putting Ash and his friends in a pitch black room. Ash calls out Charmander and tells it to use Flamethrower to light up the room. Charmander gets tired quickly and Brock finds a candle for Charmander to light with Flamethrower, but Charmander accidentally uses Flamethrower on Brock as well as the candle. While exploring, Ash and his friends find the hole made by Team Rocket earlier. They hear strange voices coming from it. In another part of the tower, a Haunter and a Gengar are watching a T.V. show on a T.V. The Gastly comes in and the three of them all laugh at the show.
Ash and his friends continue exploring the tower. They come to a big room. The lights suddenly turn on and they see that its a dining room with a long table set. There's a rope above the table with a note saying to pull it. Ash pulls the rope and confetti comes out along with a sign that says welcome on it. Suddenly, the glasses and the chairs start floating. Brock gets thrown around on a chair while Pikachu and Charmander get thrown around on some platters. Ash and Misty run out of the room and Brock, Pikachu, and Charmander try to get off. As they leave, the glasses and the chairs are reset and the Ghost Pokémon appear and they start laughing.
Outside the tower, everyone is tired from running. Misty and Brock are convinced not to go back inside the tower. Ash wants to go back in, but Pikachu and Charmander are afraid. Ash reminds them of how awful their loss aganist Sabrina was. Pikachu and Charmander decide to go back in with Ash and Misty and Brock say they will wait outside. They go back inside and come to the hole Team Rocket made before. They think Pokémon are down there. Pikachu attacks with Thundershock and it hits Team Rocket. Charmander uses Flamethrower and it burns Team Rocket. Jessie starts running around screaming because her hair is on fire. Haunter appears behind Pikachu. Pikachu gets scared and Ash turns around, but he doesn't see Haunter. Haunter appears in front of Ash, freaking him out as he checks his Pokédex. There isn't any data, so Ash sends Charmander to battle Haunter. Haunter disappears and reappears behind Ash. He thinks its Pikachu and gets scared when he sees Haunter's hand. Ash tells Charmander to use Leer. Both Charmander and Haunter make faces at each other, making Haunter start laughing. Haunter uses Lick to paralize Charmander.
Ash recalls Charmander, while Haunter continues laughing. Gengar appears through the floor and whacks Ash with a fan. Both ghosts laugh as Ash checks his Pokédex. There still isn't any information. Gengar hits Haunter with the fan, but Ash doesn't think its funny. They try to make Ash laugh, but they fail. Clearly sad, they sink through the floor. Ash and Pikachu run to stop them, but they crash into the floor. The crash shakes the chandelier above them and it falls onto Ash and Pikachu, knocking them out. Gengar taps them while Haunter pulls out the ghost form of Ash and Pikachu. They are shocked to see their bodies lying on the floor. The Ghost Pokémon take them up to the top of the tower. They admire the view and they see Misty and Brock waiting by the door. Ash listens in on what they are saying as Misty says Ash is taking too long. Ash speaks and Misty looks behind her, hearing Ash's voice. Ash pulls Misty up into the air and drops her. Brock catches her and they wonder what is going on. Ash, Pikachu, and the Ghost Pokémon fly through the air. They all laugh as Ash flies through Haunter's mouth.
The Pokémon take Ash and Pikachu to a room in the tower filled with lots of toys, even a carousel. The Ghost Pokémon weren't trying to scare people, they just wanted people to play with them. Ash has to turn down playing with them so he can continue his quest, hurting the Ghost Pokémon's feelings and they cry. Meanwhile Brock and Misty have found Ash and Pikachu's bodies, pulled them out from underneath the chandelier and are trying to wake them up. Ash and Pikachu return to their bodies and wake up. Misty and Brock are happy they are wake, Misty is about to cry.
They leave the tower the next day, Ash deciding not to capture any of the Pokémon. Haunter appears and decides to join Ash to help him win against Sabrina. Meanwhile, the other Ghost Pokémon tie Team Rocket to the carousel and send them spinning.
- "Light the candle, not me!" - Brock
- The "Pokemon Tower" in this episode seems more like an abandoned haunted house than the Pokémon Tower in the game, which was a Pokémon cemetery.
- The episode was temporarily banned from re-airing on Kids' WB! after the September 11 attacks. It was later put back into circulation.
- Due to this, Kids' WB! refused to give the tape to Cartoon Network for them to air this episode back in 2002. They have since conceded the rights to air it.
- This episode's English title is a reference to the Tower of Terror theme park ride and the movie.
- Gastly is shown to be able to create hands out of its purple surroundings.
- In this episode, Ash and Pikachu share an out of body experience; a real-world phenomena.
- The book Night in the Haunted Tower is based on this episode.
- The "Who's that Pokémon?" in this episode is Gengar.
- The mask Ash used resembles Duskull's face.
- In the last scene with Team Rocket on the carousel, Gengar's eyes are white instead of red.
- When Pikachu shocks Ash in the beginning, Ash's Japanese voice is heard.
- When Misty was trying to wake up Ash, the chandelier that was on top of him and Pikachu is gone.
- After Haunter scared Misty and Brock, Ash's bag has its colors swapped.
- When Gastly and Gengar were amused by seeing Team Rocket on the carousel, Gengar's eyes were white.