The Case of the K-9 Caper
S1, E52: On their way to Cinnabar Island, our heroes hear Officer Jenny calling after a thief. Fearing that the criminal will get away, Ash and Pikachu help apprehend the suspect using ThunderShock. However, they soon realize that the thief was actually another Officer Jenny the whole time, and that they’ve accidentally made their way onto a training ground for the police force’s Growlithe! Ash asks Officer Jenny if he and Pikachu can join in on the training, hoping that the specialized training will improve Pikachu’s battling skills. Not so far away, Team Rocket also has some ideas about the Growlithe—ideas to steal them in the name of Team Rocket!
