This is the very first episode. Ash gets Pikachu as his Pokemon. Durring the trip Pikachu was badly injured in a fight with a lot of Spearows. Ash meets Misty and borrows her bike to bring Pikachu to the Pokemon Center. On the way Pikachu did a thunderbolt to scare off the Spearows and melted Misty's Bike. Now Misty tags a long with Ash to make sure he gets her a new bike.
Pikachu was taken to a Pokemon Center to be healed. Team Rocket makes first appearance trying to steal the Pokemon in the Pokemon Center. Jesse, James, and Meowth are the only members of Team Rocket that shows up mostly. Ash, Pikachu, and Misty helps to stop Team Rocket's plan. Ash, Pikachu, and Misty continue their journey. Team Rocket is trying to steal Pikachu now.
While in a forest Ash sees a Caterpie so he catches Caterpie, Misty is affraid of bugs so she doesn't like Caterpie. Ash later sees a Pidgeotto so he battles it and wins, so he catches it. It's been two weeks since he caught Caterpie and Pidgeotto. Caterpie evolves into Metapod.
Ash still in the forest sees a Weedle so he tries to catch it. Durring the fight Samurai interruted, Ash failed in catching Caterpie. Samurai is also a Pokemon trainer. Samurai then challenged Ash to a battle, Ash accepted. Ash battles Samurai, while the fight the Weedle that got away warned the Bedrills about Ash. The Bedrills then flew over and starts to attack Ash, Pikachu, Misty, and Samurai, they all run to Samurai's cabin to hide. Metapod was left behind durring the attack so the Bedrill brought it back to their nest. Ash later rescues Matapod and drives away all the Bedrills. Metapod then evolves into Butterfree.
Ash, Pikachu, and Misty arrives at Pewter City. Ash goes to the Pewter City Gym leader to battle. He meets Brock, the gym leader. Ash then battles Brock. Ash lost the first round but with the help of some kind stranger who helps him supercharge Pikachu, Ash won the rematch. Ash got his first badge. The stranger ends up to be Brocks good for nothing father. Brock then lives the care of his family to his father and Joins Ash on his journey.