The gang arrive on a new island to witness the Conway Comet. Alexa shares with them the legend of the island. Later a mysterious woman gives them a medal as they explore the ruins. After the usual run in with Team Rocket the gang is then attacked by Gengar and Banette. They are then chased by them and Ash drops the medal the mysterious woman gave him. The Gengar , Banette ,and Dusknoir eventually realize its the Hero Conway's Medal and accept Ash and the others as friends.
They then take them to the battle field where Hero Conway battled and show them the comet. Team Rocket then tries to take Pikachu from Ash, but the gang of ghost Pokémon stop them with their Psychic (attack). Pikachu is returned to Ash and him, Cilan, and Iris dance below the comet with the ghost Pokémon.
The next day all of Alexa's footage has vanished and the mysterious woman is revealed to have been a friend of the Hero Conway leading the gang to think about who that mysterious woman.