While Ash is doing some training with his Scraggy, he and his friends are confronted by the same Sandile they met near Nuvema Town. Ash, wanting to accept Sandile's challenge is interrupted by three Ducklett which quickly snatch Ash's hat and Sandile's sunglasses.

Ash and friends have finally arrived in Castelia City. While exploring the city they run into Burgh. After hearing a noise underground, they go to find out what it was and find a wild Venipede. It is injured, and even though they heal it, the other Venipede in the sewers become upset and begin attacking the city above. Now Ash and friends must help to stop them.